For a carbureted light duty engine I wouldn’t worry. They seem to have problems most on lean running engines that are heavily used.
When I was sourcing magnum heads, I found that most of those motors have trashed exhaust valve seats. Now they are “hardened,” but they (like those from the 70s) aren’t like the stainless or stellite valve seats that a machine shop would install, rather, they are just sligntly hardened steel. If you want seats for a lifetime, spend the dough. But otherwise it’ll be alright