Where to get a new or rebuild A/C switch?

Does anyone know if the difference between the pins on the 67 & 70 & up will be an issue? The broken 1 is from my 67 & the new 1 is 70 & up. There is only 1 pin with dual connections used on mine where there are 2 seperate pins on the newer 1. Has anyone swapped in a newer switch on an older car? If so,which pin did you plug in on the newer 1? Thanks for the help.