If the engine has no oil leaks,engine bay looks clean,engine is not smoking and you take it it for a test drive as it runs and pulls well i would say it was ok. Bodywork on these cars of that era are just as important,check for around the rear arches as they are proned to rust and around the rear suspension mounts as they corrode badly around there and can be expensive to repair. Check roof is in good condition and working as again replacement roofs will cost £600 plus. Good luck.