Help with u-joint

I have a 1973 charger with a 727 tranny thats connected to a 8 1/4 rear end. the tranny come out of a 1967 car, the rear end is what came with the car. My question is this ,my rear u-joint went and im trying to find another one that goes from a 727 dive shaft to a 904 axle spline { yoke}.
Napa has one that goes from 2 5/8 to 2 1/8 but the cups are larger and wont go all the way down so that the c-clamp can go in on the 2 5/8 side . I got the Markings off the existing u-joint . In the center it has 3 letter SPR that i guess mean spicer u-joint. kitty corner from the spr on top it has W5 and on the bottom it has HS. If anyone can let me know what part number I need I would be most gratefull. I normally buy from napa so their part # would be great.

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