Yes. I have a Salamander Designs Synergy 345 - link below. This stand has space for my RC-7. My RC-7 measures 26"W, 9.1"H and 13.5"D.
Your RC-64iii is 35.8W, 8"H and 15"D.
The center speaker opening in my Synergy 345 is over 40" - so the RC64-iii will be a perfect fit.
https://www.salamanderdesigns.com/av-cabinets/synergy-model-345/
There is a fair amount of customization that can be done when ordering. It comes unassembled and goes together like any other furniture you put together.
I searched high and low for this back in 2009. I could not find anything to fit the height of the RC-7. IIRC the height of the opening is listed at 9". I had to remove the rubber feet on the center shelf to get the RC-7 in there. You won't have this issue.
I have an 85" Sony TV on top too.
They are not cheap, but good stuff is usually not.