Tubeyist sounding Pre-amp?

Cant get much for $500.00 maybe a 40 yr old CJ.Good luck let everyone know what you get.

At $500 for a tube unit, I'd think more about condition than sonics.
Also, with your amplifiers rather low single ended input impedance, it might narrow your most likely to be single ended output tube preamp options. Not sure if you need a phono stage, that'll probably add to the cost.
Here's a quick off the top of my head shortlist of inexpensive tube pres,
caveat: don't know it they'll work with your amp, or if any fit any of your criterion, but at $500 you're not going to get too many options:
Cary SLP 50
Conrad-Johnson 10
EAR 834
Quicksilver Line Stage
VTL TL-2
I'm sure there's more,
good luck!

the $500 figure was my guess at a repair to my SF Line One - it is at a local shop now and I have heard nothing for two weeks.

I have to admit I have my eye on a piece of ARC gear too, tho I understand they are very neutral sounding...

$500 to repair SF Line One is a very large figure. 
$150...200 should be about right -- $120...150 labor and about $50...80 parts

My old Ayon CD-5s with Burson single HD discrete op amps, matched 6C4P rectifiers & cryo'd EH 6H30 Gold pins. The gold pins are warmer, lusher sounding tubes. Don't neglect the importance of cables either. I found Jorma Prime sounded harmonically rich, on the warm side and liquid sounding. OTOH Jorma Origo is a bit more neutral if you don't want any more warmth.