Should I Have Passed On This Inland?

[browningautorifle]

already tried pounding (mutilating) the sling

I don't understand what the worry about that Uncle Mikes sling is. It's a commonly available sling, Brownells retails them. I'd cut it and be away with it, then you can put the correct one on. Cut it across the back side of the oiler and it'll come away clean.