Hey Dave,
Had a NP22 failure just recently, at about the 2k round mark ... http://www.canadiangunnutz.com/forum...d.php?t=564573
I had to cut my losses and just save what I could from the rest of the gun and sell as spare parts, along with the attendant accessories. It will cost you more in emails, trouble in procuring the parts, postage and shipping to rectify your problem. Cheaper to buy a new one.
Don't get me wrong, give it a try ... just a heads up on my experience.