vc1111, you can get a kit from Cabela's for the 700ML. I installed this one this fall and had no issues(double bang, accuracy,etc) with T7 in pellet or loose form.
Here is the nipple which you can buy seperately for $15 US via cabela's. It works with the breech but wether the firing pin mech is the same as a rem factory kit I don't know for sure but would assume so! (I'll post both pics)