How easy is it to keep older bikes on the road?

I'm looking at a 70s CB360 for a cafe racer build. I was wondering how easy it is to keep these things going parts wise? I'm pretty handy with a spanner and most things I can fix myself, unless they require fabrication. Then I would be stuck. At some point, it will need a full engine rebuild right? Might be in another 100 miles, another 10,000, who knows, but it can't run for ever? When that happens, is the bike dedd or can it be kept running? via /r/CafeRacers https://www.reddit.com/r/CafeRacers/comments/frsrfs/how_easy_is_it_to_keep_older_bikes_on_the_road/?utm_source=ifttt