I just bought an 88 300TE, in much better condition (and for a few thousand more). If I were you, I'd keep looking for a car about which you could know more (service records, carfax history that says it's been in salt-free areas, etc).

Also, I'd definitely get a pre-purchase inspection on any car that I was seriously considering. At least for me, it's very useful to get a neutral person's experienced eye looking at a car.

Alternatively, if you have the space & time, get the price down and make it a project car to learn on -- that's what I'd love to do =).

--da