Re:
Elastomers will happily degrade over time, theres a few different types & weights, best to strip your old forks down & examine the leftovers.
Earlier models had 2 compression elastomers & 1 smaller rebound bumper. All coloured, light yellow for soft, dark blue for hard. (medium setting was one of each.)
Later models, RC35 monobox & RC36 onwards I think, (getting modern for my knowledge) had 8 elastomers each side, much smaller clear ones.
Whatever you need I'd recommend Pace RC7 grease, using the wrong lube will slowly eat away your elastomers.
I had an old pair of RST Hi5's from new(cheap & cheerful). After a few seasons they still came into use every few years on a winter bike, after nearly 20 years the elastomers were still in fine condition, probably thanks to correct lube type aka Pace grease/Judy Butter etc.