The pin must have a head on it to keep it from coming out of its hole. Remember when you talk to the guys in the engineering shop though, an NOS camshaft is under US$80 before shipping:

http://www.ebay.com.au/itm/Tecumseh-36926A-Camshaft-MCR-OHV130-OV358EA-/190976060430

I don't know what local suppliers would be asking for one, if there is any local stock.