I'll provide you with some information regarding repair and we'll go from there. There is a valve replacement available (product number KN50-Y027) as well as a repair kit for the pedal (product number K25-0330). I cannot be sure which pieces you're looking to replace, but here is a picture of what is included in the repair kit: http://www.etundra.com/ShowDocument.aspx?fileId=277951 Please let us know if this does not solve your repair needs and we'll try to work with you further!
As of today, 3/3/11, we have 3 of these knee valves in stock. The best way to check current inventory is to call our sales department at 888-388-6372.