MGB-
Not speaking from personal experience, but I've heard good things about a company called The Wilderness (mentioned here before)that specializes in outdoor/shooting products. Here is a link for their sling:
http://www.thewilderness.com/GILESLIG.HTM
Is anyone aware if there is such a thing as an ambidexterous sling? Seems that would be pretty handy on a shotgun.
~ Blue Jays ~