I have a slightly used KKM .40 conversion barrel for a G29. This will let you shoot .40 in your 10mm G29 with no other changes! Same mags, same springs, it works great. They list for $175 shipped on the KKM website and I'd do $125 shipped Paypal OK. Reasonable offers will be entertained. Barrel is as close to perfect as can be, but it has about 100-150 rounds through it. I just don't have a 29 any longer
Al