Hi Cyber Jack
That's my main worries with the Kirby is sourcing parts, besides gaskets I don't think it would need anything major replacing just a carby clean and some gap adjustments and a valve lap. I like the fact that it's got a cast iron sleeve and I'm thinking the HP might be slightly larger than my Briggs. I might just do a minor rebuild service of the Kirby rather than a full teardown just to see what it's like as I would rather put more money time and effort into the deck and blades, the guy I bought it from said the engine ran good until it wouldn't start. Who knows the Kirby might win me over once I have a look at it.
I think my handle plate and chain cover are just rusty not black, they look to have green paint under the rust. The rest of the paint work dident rust cause it was covered in years of engine oil, it looked alot worse before I gave it a clean