Sweet score! A buddy of mine down here in Lethbridge picked one up this spring. His ran fine for a while, then developed a mysterious electrical fault. we havent been able to pin it down to any single source yet, and its been off the road since July unfortunately.
Old Honda fours turn into really sweet cafe racers, just do a search for CB500 cafe racers and you should be able to find lots of inspiration if thats your thing. Even just a cleaning up and de-rusting will turn this into a really nice little bike to start off on.