No experience with older models unfortunately. On the plus side they are incredibly straightforward machines so assuming everything is structurally sound and there are no major leaks, I can't see it ever taking too much work to get one back up to speed.
Struggling to think of anything that could go wrong that wouldn't involve replacing the heating element, new pressure-stat (not sure if they had one on the older models) or some new gaskets. That one does look to have some pitting on the chrome which I imagine is expected given the age.
Any particular desire for such an old model? I'm quite pleased with how the design has stayed consistent over such a long period of time (aside from the base really). Just asking as my new one was less than that (not sure how much market rates vary across the Atlantic though).
Edit: Just had a quick look and christ the new ones are expensive in the US. Never mind the above paragraph!