Guess they weren't very popular over there. They were here in Australia - once upon a time when Smith still made them. I have 2, a 586 6", and 686 6". They were especially popular here in Oz for service match. Service match is kinda like your PPC, but allowed adjustable front as well as rear. The reason the adjustable front was popular is it allowed a simple repeatable adjustment for each yardage, same as the aristocrat rears do for PPC. Service match here is about as popular now as PPC is over there these days!
EDIT : I bulged the barrel on my 586 about 3 years ago, it had well in excess of 100,000 rounds through it. It took me 3 years to find one, but about 6 months ago, I found a new 6" AFS barrel. Couldn't believe my luck. Snatched it up and will restore the old girl when i get a chance.