Lose exhaust valve seat

Some time ago I peened in a loose seat on an 18 hrs Briggs L-Shape.. It was all good at least for about six - seven months, well guess I didn't do it good enough.. I was hoping that it was the opposite side and my fix would hold. I ordered some seal lock but then figured tired of tearing down the engine for something so simple so i decided just to take it to a machine shop.. After all the phone calls I could never get a straight answer for an oversize seat, even when calling Briggs themselves.. Whats up do they just want me to buy a new engine? For $120 bucks I was told that the oversize seats are available thank god... I will get a new valve job included plus one head bolt that was broke off inside along with an easy out taken out... now it will be up and running again. Sometimes it pays just to spend a little extra and have it done right... Now I suppose that expensive seal lock will just sit in the shop who knows maybe I will find a use for it.