<VV> Have Worn Out 110 Block

[Michael Mauro]

Rebuilding my 67 110... the problem: with a new cam, the journal clearances (specifically the one at the rear, opposite the cam gear), will exceed (by several thousands) the factory spec... the block is worn out.  
Looking to Purchase... 1) a NOS block (I know, good luck with that, but I DID find a NOS FC block, several years back); or, a good used block (verified, by mic, that the cam bearing openings are near factory spec). As an option, need to split the block, surface, and have line-bored... Question: has anyone done, or have done, this (line-bore) operation on a Corvair block?  
Thanks in advance... Mike Mauro