Mac tools has a repair service; they have a flat repair rate. Give them a call and see if it is cost effective.
Consumer Repairs
Mac Tools operates a world class repair department to assist our Distributors, Franchisees and Consumers with repairing air tools and some electronic tools. If you are unclear if a tool is repairable, contact Mac Tools Customer Service at 1-800-MAC-TOOLS. Flat repair rates have been established for most tools.
http://www.mactools.com/CustomerServ..4/Default.aspx
They still sell that model: http://www.mactools.com/product/tabi..ir-wrench.aspx
I have the same gun; I would guess that it is based on the IR 212 3/8 impact gun, if that s the case, here are some prices on parts.
parts list:
http://www.irtechpubs.com/ir_pdfs/To..584587_ed4.pdf
anvil: Ingersoll-Rand 1702-A626 3/8' Impact Anvil IR 212 $45
another place: $34.95
http://www.parts4tools.com/store/page17.html
ring: Ingersoll-Rand 1702-425 3/8' Socket Retainer Spring Clip IR 212' $2
tune up kit: $28
whole new IR 212 gun: Ingersoll Rand IR212 3/8-Inch Drive Impact Wrench $128
https://www.google.com/search?q=inge..w=1280&bih=937
I would also contact other air tool repair places; they may have lower flat rate repair prices, that is a very common gun.. so, you might get lucky. Again, a flat rate; many times is a better deal then replacing all the parts yourself, only you can decide that.. once you figure out what the flat fees are. Good luck and let us know what you end up doing and how the repairs, flat fees and repairs end up going.