66 A body driveshaft

I am in need of a driveshaft for my 66 barracuda.it is a 904 auto and a 8 3/4 rear which has a U-joint width of 3 5/16-ish. Best I can measure since I don't have one is from center of rear u-joint to back of transmission housing is 52 1/2". I live just outside of Portland, Oregon. thanks ahead of time for any help.