My number does not agree with Jerry's for some reason. Perhaps his is a newer, replacement number (as frequently happens) for the same part. The number for that bearing housing from my original B/C mower manual is 308377. I was able to get a NOS one a few years back for my mower, along with NOS mating straps. I suggest you also look into the condition of the two mating pitman straps (301761). If there is any noticeable wear from a perfectly round, tapered opening, I'd plan on replacing those also, especially if you are able to get a bearing housing in good/new condition. That joint is fairly critical to keep snug and prevent premature wear. Once the joint loosens up and either the nubs on the housing or the mating openings in the straps start to go out-of-round, wear proceeds rapidly. I now check that joint every time I use the mower, sometimes even two or three times in a day.
Due to the fact that those items are wear parts, finding decent used ones can be a problem, although even worn ones could work for a while. If you want to investigate the possibility of NOS ones, check an AGCO dealer. Sandy Lake Implement is one such dealer. However, be prepared for a price shock - if any are still available, $$$ are involved - likely more than the cost of an entire used mower assembly.
BTW, the bearing housing, 308377, does NOT include the steel outer race for the bearing. That's a thin, plain steel sleeve that is inserted into the bore of the housing. It's a separate part, number 604476. Perhaps you can reuse your old race if in decent shape.