I have a 425 bare block casting number 386525A that I think is a 1965 block. Standard bore. Measures 4.127" with calipers. It was cleaned and checked about 20 years ago and has been in the shed since so it does have a bit of surface rust all over. I am in southern California so shipping would be expensive if you are not close to me but I do have the ability to ship if you really need it. $75? Offers? If you are local and want it, make an offer. I want it to get used and I would hate to see it scrapped.