HELP - Cragar SS Lug Nut Washers Keep Crushing - Need Alternatives!

I searched and have seen this problem discussed before but have still not found a definitive solution. Called Cragar just now and got no help from them.
I have the small bolt pattern 5 x 4 wheels which use the smaller 7/16" stud. The lug nuts have an 11/16" size hex. My washers keep crushing even though I've been careful to use a torque wrench and not over-tighten them. The wheels constantly loosen up because the soft washers just crush down. I've tried searching for Stainless washers but can't find them in the smaller size (.60" inner diameter).
Planning to have the car back on the road this Spring and need to find a good, safe solution for this. It's gotta be a pretty common issue...?
Thanks for any help!
-Doug

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