For a few hundred bucks you can get a Pangea wood rack with 4 or 5 shelves. If you think you have vibration issues, use footers or an isolation pad. It is ridiculous to spend megabucks on a rack.
+1
Better to spend the money on nice custom book/LP/CD racks and other room treatments.
Sorbothane, points and VPI bricks in a Pangea create an absolutely dead support. ZERO tube amp microphonics.
IMO, anyone with the TT the same room as speakers capable of realistic levels is asking for trouble. [My last TT set up was in another room with the ARC SP6 with support anchored to the concrete floor... in the last century 😉]
None believers can digitize the preamp output with the power amps on and off, then compare. Any delta and you gots a problem