U-Joint trouble

I have a 1993 Dodge Dakota 4x4 and I can not find the u-joint for the rear drive shaft. The ones listed in the book at the dealerships are not the right ones. I have a 2 31/32 by 3 3/8 inches without the caps and not the dealer nor the parts stores have anything like it. The caps are also all grooved and that seems to be a problem. I am going crazy can anyone shed some light??

Take your old U-joint and go to a parts store with experienced help. Take all parts.