I am planning on installing unions on the water supply line of my backflow prevention valve so I can remove it during the winter to protect it from harsh winter temps and copper/brass thieves . My concern is that the pipe coming from the basement is only 5 inches long. Is that long enough to install a 1 inch union ? I know that I will have to cut out enough pipe out to make room to sweat on the union fittings. I will attach photo. Also, Home Depot and Lowes doesn't sell 1 inch unions. My local plumbing supply gets $20 per union. Is that a fair price?