There's a book that has details of all the the info you're looking for, but what it's called escapes me at the moment. Might be something as simple as the "History of Ruger .22 Pistols" but I'm sure that's not it. I've read bits of it, but don't own a copy.

The Mk IIs, I seem to recall, had a small over run, and were sold on the civilian market- 5? 50?, not many.....