OK, I misread your post, the knob isn't bent, but the control shaft is. Sorry
Well, have you called Uniden America or one of their dealers such as Bearcat Warehouse or ScannerMaster? Or any larger dealership?
In addition, Uniden America *may* still have a stock of parts available if you send the radio to them for repair.
If all else fails, keep looking on ebay or any other similar site for a broken radio that's good for parts only. I *believe* but do not know, that the BCD 396XT parts, for the most part, are identical.