If you’re looking at it as a hobby car that will also fill in for your occasional driving needs, I’d say go for it. I bought my '86 Accord when it was 20, and it’s given me no trouble at all and I would feel perfectly fine relying on it as my only daily driver. I see no reason why a well-maintained example of a Supra wouldn’t be reasonably reliable.
I do think 8000 is a lot of money though-- I know these cars do command a premium, but that is an awful lot for a 20 year old car. If you don’t have your heart set on that particular model, you may be able to get a lot more car for your money. I was thinking maybe the Nissan or Mitsubishi sports cars would be similar and could probably be had closer 10-years old in your price range.
Also, don’t pay a lot more for low mileage-- once a car gets that old, you have to worry more about age-related wear and it’s no longer a matter of there being X number of miles left on it.