I'm on "re-stuffing" team. It's not very difficult to do , once you get the hang of cutting and gutting the pots. They solder back together easily.
I just think it looks cool and is a very unique piee of electronics construction history-if you like that sort of thing.
Most are triple .05 uf/400v. I think the larger ones in the rear were .1uf/400v and .2uf/400v. Easy enough to figure out since the capacitance is written on the pot.
The voltage input is 285V max , so 400 volt caps will be fine.
JIm AC2EU