The bearing is included. It's located just inboard of the inner CV joint and is pressed onto the shaft. I'm can't tell if it could be responsible for your noise but if you suspect it inspect it for "crunchy-ness". Also you could see if the sound changes after lubricating it by inserting some light lube via a hypodermic or perhaps by peeling back the dust cover. This is a common band-aid fix for the center carrier bearing on 240 driveshafts. A search on the topic in the RWD forum should produce some hits.

The bearing will be labeled with a manufacturer and part number, probably an SKF. You could get a replacement from a bearing supply house. I would advise against it because you would have to deal with pressing the old one off and the new one on. The press fit is critical. Too tight and you'll compromise the bearing, too loose and you risk the shaft coming loose from the carrier. When the latter occurred on my 850 the driveshaft came free from the transmission, leaving me stranded.

Good luck,
Will
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