~50kW variable speed alternator/generator

Since this board has a pretty wide range of specialists, thought I would ask a technical search question-

We are looking for a generator that has ~50kW output (pretty large) that has a speed range up to 5000rpm.  Which counts out most of the alternators/generators I can find that are fixed speed output based on the desired frequency of the AC.

AC or DC does not matter- but the signal would be corrected to a DC output in the 400-500V range (I'm not sure).  

Yes, this will feed a battery.  With an ICE.

I've found one generator/alternator that's 30kW, and had a max speed of 5400rpm, and it is marketed in the same field it intended to use.  But other than that, more clever google search functions keep coming back with things that don't fit what I'm looking for.

Any ideas?

You need the MG2 from a 1st or 2nd generation Prius. It makes the power you're looking for at the RPM you're looking for.

In reply to chaparral :

I'll suggest that.  But this isn't for a personal project, so using brand new, off the shelf, parts, is ok.  I was hoping that someone worked in the large generator field, who may know of something.

Bump this for the morning crowd- I'd be shocked if this stumps the GRM crowd.