Carrier bearing?

Inspecting why my '87 D21, 2WD Z24 "shimmys" at speed, I find a dry rotted rubber ring going around my driveshaft at a joint. Starting at the transmission and going rearward, there's a joint, a shorter piece, then another joint. At this joint, the front side of the rubber looks fine, but the rear part is cracking.

Is this my carrier bearing?

Nissan shows no such part, but for $75 they list a center support bearing. Is this really all I need?

It looks like I'd need to take out BOTH pieces of the driveshaft, transmission to differential, as well as the "strap" going over the problem joint. I saw the advice about marking it with a chalk line to preserve orientation, and not bending the dogears. No special tools needed?

(Thanks to our resident Nissan answer man here)

it is called both ..