This one was from 2000. It's a high end programming keyboard line that's streamlined for developers and speed typists. The newer models sell for about $250 today and are designed for low friction and optimal ergonomics for speed.
When in doubt, look up the model numbers on eBay to look under "recently sold listings" and you'll get a gist. If you have a lot of old equipment, I'm sure you have a few gems mixed in with a bunch of standard stuff. A bit of research/inventory assessment will help guide you to the cream of the crop.
It's all about supply and demand with the vintage stuff. Collectors or irrationally faithful techies for their old gear can be rabid for certain vintage electronics. If you have the only one listed on eBay, it's your chance to name your price and see what the cat drags in.
Thanks for the extra info. I will do some digging in the storage.
Make sure you keep them away from humidity. Over time it can damage the boards inside. That happened with a $400 sale of mine of a brand new camera... it was 15-20 years old, but the internals had gone on the fritz for the LCD display because of moisture that somehow got in the package from being in a basement.
Unfortunately the area where they are stored can get a bit damp in the winter. Maybe bad news.
If it's manageable to get a dehumidifier you can regularly dump, that'd help, but I'd step on the gas and sift through to pluck out the most valuable stuff for the short term. It's not often that the boards get this issue, but it's certainly a possibility if they've been in those conditions for a very long period of time.