Is a ’94 580k “too old”?

Hi everyone, Been a little while but that just means my 25k hour deere 310d has been working pretty well if I haven't been on here crying and asking what to do. So I have a bit of a different type of question now, a colleague has offered to sell me a 1994 580k for around the equivalent of 10,000 usd. I'm in Costa Rica and that's a pretty good price for something that still has tags and exists on the books. The thing is beat to hell but still works, same as my '97 310d. My logic is, and this has also been suggested to me on this forum, is that it'd be a good idea to have two old hoes just to have a spare. The thing is my primary source of income and when it's out of commission I'm back to construction work that's fine but doesn't pay nearly as much. However I know that hoes can tumble down hills, grind transmissions to smithereens, and occasionally even drive themselves away. All of which would leave me in the "screwed" category for a while. So is a 94 580k "too" old to be a good idea as a spare hoe? Does it ever get difficult to obtain parts for these things? In ten years will I be able to sell it to some farmer that doesn't want to do anything commercial with it? The machine that's been offered to me tumbled down a hill a few months ago but it got put back together and seems to be okay. I know the mechanic that rebuilt it and id ask him what he thinks about its condition too. The other thing I'd consider is something like a deere 310e or perhaps a new Holland but that'd be more expensive by a lot and an unknown quantity, whereas I know my buddy's hoe and he drives it every day. Sooo I guess after this long ramble the question is if parts will still be available for a 580k for the next several years. Thanks!