Cast iron doesn't wear out. I think I'd rather have a 70 year old American made piece in good condition than a brand new item made by a 12 year old indentured servant in some backyard forge in a third world country. If the gasket surfaces need a little cleanup, a belt sander and a straight edge will handle that little chore quickly. Yes, any muffler shop can install a reducer to adapt the pipe size down to 2" if you can't find manifolds that suit you. Too-large exhaust pipes on a small displacement engine slow down the gas velocity and create flat spots in acceleration at low and midrange RPM. They're great if you plan to run wide open throttle and high RPM all the time.
When I replaced a 235 in a 58 Chevy DelRay coupe with a 61 Corvette 283 in the late 1960's, I bought brand new 2 1/2 inch rams' horn exhaust manifolds for a 300 HP 327. It was a mistake.
Jerry
