Before giving up, have a go at it with one of JB Weld's products. They make good stuff.
Lay it on, let it cure the prescribed amount of time, sand it flat, install it, and see what happens.
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Maybe contact them for ideas on which of their products they think might work best.
This looks like it might do the job:
http://www.jbweld.com/product/j-b-pro/