LM — an LCA is an LCA?

Long story short, bent RF LCA needs replacement on NA Miata. (Backstory, my incident-free streak at Tail of the Dragon was ended by bumping into a trashcan while pulling off at the overlook area. Stickerbomb is apparently camo to me.)

Interweb shopping barfed up a dozen cheap options ($50-$65) from Summit and Rockauto, and a handful of OEMs in the $200 range. All seem to include bushings and balljoints preinstalled.

I can't spot any distinct advantages of OEM vs say the Delphi from RA... this looks like a good inquiry for The Hive.

This roadster is stock, and basically a weekend joyride at this point — no more track or AX ("don't need nuthin' fancy"), but I don't want to redo the job either ("price is what you pay, value is what you get") and these should last the life of me/car (unless there's a cart corral out there somewhere just itchin' fer a fight).

Still with me? Congrats, you made it to the audience participation round!!

[Q1] Which should I get and why? What would you get and why? (I suppose technically that's four.)

[Q5] Should I replace the intact LF LCA at the same time so the bushings are similarly supple? (None are bad, but most are original.)

[Q6] Is the part really the same from 90 thru 05? (I used to know this.)

[QB] bonus (longshot) Anyone happen to be overstocked on the part(s) I happen to need, and looking to offload?

Thank you for your time and consideration. Gratuitous pic follows.

This is good line of questions. I've used mevotech on other platforms and been happy, but don't know if they even do miata. So I'm watching to learn. 

Excellent gratuitous pic.

I haven't investigated the aftermarket stock replacement alternatives, so unfortunately I have little to say. It is just a couple of pieces of stamped steel, so as long as they didn't go with a lighter gauge you should be okay. Note that there is no ball joint in the lower arm, it's a separate part that is bolted on. I would recommend OEM lower ball joints, the failure mode is poor and it does happen.

I'd be tempted to take this as an excuse to do all the bushings. I know it's a fair bit of work, but after experiencing some before/after I have become a strong believer in fresh bushings. They're a big part of what makes a car feel old. The front lower arms take a lot of braking and cornering force, so if you're only going to do a couple of bushings those are the ones to do.

The parts are interchangeable from 90-05, but not identical. The NB ones have a single shear sway bar mount instead of double shear, but that's not a big problem. The NB ones are also reinforced, especially the 2001-05 units. Same geometry, just less likely to buckle under hard use.

No spares, sorry :)

I have used a Moog uca from rockauto on my NA. Fitment was good, balljoint was good and it has been working well for over a year. 
 

I think one of the bushings needed to pressed in another 2 mm to fit properly but that was the only issue. Definitely recommend. Hard to beat at about $50 each. I imagine the lca will provide similar results. 

A lot of aftermarket control arms aren't exactly dimensionally accurate to OE, not even left vs right, so I'd only stick with those that are known quantities if you do go aftermarket.

My experience on the Ody is that Mevotech is absolute dog E36 M3.

Mevotech kinda humped me on my Express Van.  I needed bearing hubs, and they advertised themselves very well.  14k later, they were both trashed... just outside of the one-year/12k warranty.  OEM replacements have now been on for 40k and they're still perfect.  That is not to say their LCAs are trash, they might be great, but the big question mark is which ones have ball joints and bushings that are worth a darn.  At the shop, we often used to get whatever was cheapest from WorldPac, and some would show up with ball joints that were loose enough to fail an inspection.

The moog LCA replacements for my Grand Cherokee fit well and ride well. Big improvement over the original >150k mile bushings.

The disappointing part is that after less that a year the ball joint boots are cracking and look like they will eventually split. . 

In my experience, Mevotech and other RA (ish) brands have terrible quality rubber.

I would check with one of the reputable Miata salvage shops for a used OEM part.  I got one off eBay once, but that's a little more of a crapshoot.

https://treasurecoastmiata.com/i-11654993-90-97-mazda-miata-front-lower-control-arm.html

And, as Keith noted above, bushings will make a big difference in how the car rides and drives.  It's a big job, but worth it.

The Moog upper control arms were a perfect match to oem on the Miata. I have the jigs from Advanced Autosports and checked them prior to install. 
 

I used the higher end Mevotech upper arms on my Silverado. I forget if I used Moog or mevotech for the tie rods but all of them have Been working fine towing 9k for the last 3 years. 
 

Ymmv of course