Custom 1-piece driveshaft vibes

[t120r]

Hey guys, I have an SASed 1990 Ranger using '79 Bronco running gear. It's got a bad vibration at 80-85km/h. I ripped apart my whole rear axle and reset the backlash. Closely inspected the driveshaft/u-joints and greased everything. Took it for a test run and the damn thing still vibrates. So I was lying underneath it and started twisting and pulling on the driveshaft. There is play in my slip yoke. Bummer... But at least I found the problem. I take the shaft off and find out that there is only play in this spot of travel. Go figure. So now I need to replace the slip yoke. It's a '79 bronco shaft that was custom made to fit my ranger. I can easily get the female end that holds the U-joint, they're even cheap... But what's the point? I mean I would be naive to think that only one end wears out. Does anyone know where to get both ends? I've been looking at a place called driveshaft superstore, but I'm not keen on chinese stuff... Hard to say where they get it from...

http://www.driveshaftsuperstore.com/Drive_shaft_long_slip_yoke_and_spline.htm

Is there anyone on here who deals with this stuff?