Vintage Marshall cabs, esp from the 60s will command big prices since they’re highly collectible. Tolex/ no tolex, doesn’t matter. A 1968 cab beat to hell but has original speakers will still get 4K, maybe 6K. If you buy one, and re tolex it, you just lost money. Just the way it is, They aren’t making any more, same with the Pulsonic speakers.
The vintage Marshall cab/speaker market is just as intense as the vintage Marshall amp market…maybe more so since 60s cabs with original speakers, wiring loom, tolex, grill are fewer in number than the 60s amps.
I’d put the Marshall cab market like this:
86-1990 800 cabs, 600$
81-85 800 cabs, 6-1000 depending on speakers
74-1980 JMP, 1200-1500
71-73- 2K or more
66-1970-3K on up to 10k if the M20s are in a 1966-67 cab and it has og tolex, grill
The vintage market is a whole different animal vs reselling a modern built cab