Have someone decent spray weld the hook. Cole Haugh in Indiana does this at relatively low cost...he has done 2-3 guns for me.

You can use shim stock and stick it to the hook with some of the Loctite compounds used for bearing surfaces. I think Loctite 680 is one of these. Check for the latest Loctite recommendations. It works, I have done this on two guns. These were .001 or .002 shims. .002 is a lot of play, I would be surprised if you actually have .007!