SirMarc, unlike other threads on headfi, this thread isn't full of people who speculate about stuff they've never heard
At a high level, the odds are a decent 70's receiver will outperform a late 80's mass market receiver. The late 80's wasn't a great period for mass market stuff. But that's just the macro view.
Your unit sounds like it was a good one, though, so it may well be hard to top. No possible way to say without hearing it.