Correct terminology is 'inner magazine tube assembly.' The BAR22 and BPR22 used the same part, we occasionally have them for around $23.
Browning never made the BAR in 22 magnum. They made the BPR, which looked liked the BAR, from 1976-85
22 years old
They currently make a Left handed BAR, but not in .22-250 Check with Browning customer service at link below to verify about previously made LH Bar's.
50- 300 usd
Try egunparts, gun show, gun shop.
Try e-gunparts.com
After much research, a manufacturer could not be found that made a buffer for your model. Perhaps a request to Browning would be in order. Try a Buffer manufacturer and request that they make one for your .22 BAR.
Depends on the condition and if you have the original box.
50-500 USD or so
Try e-gunparts.com or MidWest Gun Works.
50-500 usd
20-2000 USD depending on specifics