HA! Looks like the bolt that I found on the brake lever of my current project: . . .
I can imagine someone needing a rear brake and doing the best they could at the time. It's not easy to imagine this, but I can. (Personally I can ride a fair distance with only a front brake. This is not a recommendation.)
When I try to imagine why there's an SAE bolt in my kick-start, it requires me to imagine that the electric start doesn't work and they really need to find anything that'll make the kick work. It becomes a really sad state of repairs that require an SAE kick bolt.
As far as chasing the threads, I may be ahead. The SAE bolt is short, too, so if I start a metric thread chaser from the bottom, there's 6mm of unmangled thread before I get to the mushed part. The bolt is visibly deformed, so the bore may be OK. The rest of this engine has other examples of this kind of care, so the kick in the opening pic is a spare part.
More pics of heart-sinking repairs???