I'd say 5% or less in any "stock", uh oh I said the S word, condition. Probably much less. I need to quit selling parts again! Get building.
From what I've seen in magazines, internet, anywhere since the 80s there aren't very many left. A lot of K Spoirtsters, and SportyKs, and Choppers, Bobbers, Basket Cases weaved together. After I jotted down the Hi story of the Model K for SPORTSTER.org in 90s, posted here now, I got to meet many K owners around the world. Not that many, no. And not stock. You can't show me 35 56 KHKs 10% or even 15 stock ones. bet you 100$ is that legal Dave?