A roller cam core can be made by splicing a piece of 2 1/4" round stock such as drill rod or tool steel onto either side of the distributor gear, and turning them down to make bearing journals and lobe blanks. Even the fuel pump lobe can be put onto the shaft by a cam grinder if you choose not to use an electric pump. The maximum lobe lift will be determined by the diameter of the #3 cam bearing journal, which is 2.029" on a 235/261 cam. A 36" piece of 1018 alloy steel costs $95.00 on Ebay, with free shipping, enough to make both halves of a spliced-together cam core. 1018 can be surface-hardened if desired, by case hardening or carburizing, leaving a hard surface and a tough core.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!