904 output yokes

Any other source for 904 1310 or 1330 output slip yokes other than Mancini? They are backordered and I need to build a 7290 driveline for my rearend swap. I already have a 7290 pinion yoke for the rear. Also, should the clutch plates in the sure grip have a friction and a steel? They all seem like they are steel to me.