I no longer checker guns, my hands can't take it anymore.
However if you don't find someone to do your checkering I do a front strap treatment using my mill. I call it Speed Grip, it works every bit as well as 20LPI checkering but is not as abrassive to the hands.
Here's a picture of a gun with Speed Grip on the front strap.
Regards
Bob Hunter www.huntercustoms.com