Independent shop can I supply parts.

You do understand that profit is what makes the economy go around, correct?

If you spend some money in his business, he just might be able to spend some money with your business.

I know profit is a dirty word in modern society but this is how we managed to move society forward to the point where it is now.

I'd just email and explain that you want to put known quantity parts in the car but don't have the time to do it, can you give me a labor only quote for X job. That way they can adjust pricing, shop rates, whatever to make their margins and you're not going to come off as someone going for the cheapest thing on earth. In my experience doing that some shops are gonna decline, some don't read your email and send a quote with parts, some are cool with it after asking some questions to figure out how much of a pain in the ass you're going to be.

Edit: Hah, this experience is pretty much all based on the Mazda racer discount too.

My mechanic shop is a side gig from his regular dealership job, so I typically bring in the parts (usually oem honda/acura or high quality aftermarket parts) . It's been working out fine as for the most part I've been able to correctly diagnose the problems, but not having access to a lift and being inexperienced with the install, I leave the job for him to do. From talking to him, he's had issues with people bringing parts that don't fit right, but bringing in OEM parts he enjoys b/c for the most part it just works. 

I price a job to make a certain amount of money off it between the parts and labor price. Generally if someone gets my labor quote and then wants to bring their own part, it turns into i undersold the job and now i don't want to do it. This is with me charging retail for the part and just making what i save by getting it at 'my price'. Then if any warranty issues come up they're not happy with me because the warranty is only on the part and they're still getting charged labor and by the way come pick up this part i just pulled off your car and go get me a new one and maybe now i have to move your disassembled car out of my work space because it's going to take you who knows how long to go get this thing warrantied. Or i scheduled my whole day for your job and then find out you bought the wrong part and i only found this out after i took your car apart because it was buried and i couldn't visually verify it. Etc etc. 

In general it's not worth the hassle for a mechanic/shop to deal with someone who wants to bring their own parts. It's always going to go sideways eventually and most decent techs/shops aren't starving for work and can afford to turn away things that they think will turn into a hassle.

Where I am I have two shops that are completely honest and both allow me to bring in parts or if sourcing them the prices are generally within what I would have paid.  I only use those two shops for work for all of my cars. I recommend them to everyone that asks for a good shop. One of them I took my 2001 corolla to for the timing chain replacement at 200k miles. It was 900 bucks. because I had him source the parts he bought the oem complete kit at $300 bucks. I had sourced quality parts for about half that.(and he would have just charged me labor had I gone that route. ) I paid the full bill without complaint knowing the engine will easily go another 200k with the new parts and I know he does great work. It didn't hurt that I felt like he has saved me way more money than that over the years.