I am installing all new bronze thru-hulls on my project boat. I got 1-1/2" and 1" bronze Groco thru hulls and they have nps threads (national pipe straight). I searched the store here and not having much luck finding nps thread ball valves....most are npt. Nps on one end and npt on the other would be perfect since I will need a barbed hose fittings too. Can someone point me in the right direction on finding these parts?. I don't want to spend $100 on one ball valve either.