I actually did some searching since I was curious about the designation. Apparently SR22PB is the catalog number but it is still only stamped SR22P on the slide. The reason I was so curious is because I just got mine about 2 weeks ago and the slide is marked SR22P without the B. Apparently this is the case for all of them though and upon digging back out my factory case it does say PB on the sticker...odd.Not sure what the B stands for, the earlier model was the SR22P so I think this is just the newest model. I can get a NIB one on gunbroker for about 300.00 delivered plus my 10.00 transfer fee but wouldn't mind paying a little more for a local pick up.
The local Academies I frequent seem to have them in stock for about $357 incl. tax.
You will pay that or more at a gun show.