I found a guy who has done the pad welding several times before. He does excellent work at a reasonable price and he can refer me to another guy who has done the close tolerance pad milling on Vespa cases.
Here's an example of his welding.
I'm thinking of trying it because I've got an otherwise good P200 motor except the top end and crank.
The wrist pin bearing disintegrated and ate the pad, so I'll be doing the bearings & seals as well.
chewed up good, nice deep grooves
these nasty bits probably did some of the chewing
they were hiding between the seal and the bearing so they must have passed through the seal