Look into used NASCAR drivelines. We have bought many from various vendors and they have them in 1/2” increments in 3” and 3.5” diameters. The majority of them are from dynotech and have 1350 spicer joints and a turbo 400 style yolk we sell. Last one cost a whopping $90! Inland Empire is a good source for yolks and/or drivel we as well, they support us west coast racers.