Hi,
I saw this thread only recently. Yes, I know who the Yankee Saddler is/was. He was a good friend of my fathers, a master saddler from the UK, and I can remember him visiting us in Bracknell sometime in the 70s.
I remember his first name was Don, and yes, he made many gun holsters, all hand stitched beautifully.
I'll have to ask my family if they can recall his surname.
If you have some of his work, I'd hold on to it if I were you, it's classic.
Have a good day.
Diva