None of these engine parts are obsolete. Your local automotive machine shop can usually beat any restoration catalog supplier
prices.
Note; you are looking for a shop equipped to bore, turn cranks, etc since you're likely to need this service anyway--they usually give you jobber's price if you have them do necessary machine work. I can tell you that you're looking at a minimum of $900 to $1100 for a rebuild and that's assuming you use your old cam and lifters and assembling yourself. These old stovebolts aren't cheap to rebuild!