Best Options In A Balanced Preamp Under $1500.00?

I'm in the process of helping a friend who is a music aficionado, musician and budding audiophile build his first system. As a relatively young guy, his budget is somewhat limited. He will be using a pair of Monarchy SM-70 Pro monoblocks for amplification and now needs a balanced preamp, as those amps truly need a balanced signal for optimum sound performance.

If he had a bit more to spend, I could advise him, but in this particular range of price, I'm not as well versed. What would you recommend in a used balanced preamp as his best option(s)? I say used, because I am not aware of anything in that price range that can be had new, and also to maximize his investment. Any assistance would be greatly appreciated. Thanks in advance.
There is a used Musical Fidelity M6PRE for sale on Agon right now priced at $1500. M6PRE an excellent preamp for that money.
The PS Audio PCA2 is another you could add to the list. There's one listed here now but the price is a good 40% too high IMO.
I owned one for a while, nice smooth operation and neutral sound.
You might look at the YS audio balanced a2 for a grand new.I just got one 2 days ago for my 2nd system upstairs.
Kavent S-33...rebadged Vincent SA-93...maybe hard to find. I'd check out the Jolida Fusion...not expensive, balanced ins and outs, remote, tubes. What's not to like?
Cary SLP 03, one used on the Gon for $1300. Great Cary sound, one set of XLR inputs and one set XLR output.