I don't think that RX23 and RX26 were ever officially supported by dec on any pdp-11. I've never seen any dec software released on them anyway. But, there was a fellow in eastern europe some years back that I helped who had some 11/23 based machine tool controller with a non-dec disk controller that ran off of a 720k 3.5" floppy.
I too would be very curious about RX33 on a unibus machine. I have the RUX50 print set on microfiche. I think it's the same vintage as RQDX1, which doesn't support the RX33 either. Were there any non-dec unibus interfaces that would support it?
Lou
