Or why even bother with the usual racks? I was doing a bit of poking around on nVent/Schroff's website last night, and you can slap together a bespoke 84 hp rackmountable for next to dirt. Granted, this trick requires a little knowledge of how subrack assemblies are outfitted and assembled, but just look at that as "knowledge gained"...for a big discount, too!
https://schroff.nvent.com/solutions/schroff/applications/19-subracks-and-chassis
Note that you can go as basic...or complex...as you like. 3U or 6U, the ability to add tile rows (with a little ingenuity), bespoke depths, bespoke busboard placement, and so forth. No, not as easy as just snagging something like...hmm...this: https://www.perfectcircuit.com/doepfer-a-100g6-6u.html ...but at the same time, you should remember that what you're looking at there IS what's at Schroff's site also. But it doesn't cost $530.