WR426 Blown engine

[Reedus]

Bad stroke of luck happened the other day on the old 426. I had a rock flip up and crack the water pump cover without me noticing. Drained all the fluid and ten minutes later the bike seized. Question now is what to do with it. What am I looking at worst case scenario to rebuild it? Supposing and hoping it is only the top end, is it possible to replace the cylinder jug and piston with a 450 jug and piston. If I do tear it down and rebuild, I will probably get rid of the manual decomp cam and get a hotcams auto. Any ideas or suggestions on what to do with the bike. Is it worth the tear down or should I just sell it with the blown engine? Thanks for the advice...

[William1]

Bore, a replate on the barrel, new piston and rings is probably all it needs. Did not lose oil, right?