0.5x1.5 6061 bar stock. Cut the holes, split lengthwise, drill and tap 1/4 allen head bolts. Cover the lines with a round of rubber mastic tape and you're golden.
Stainless line (1/4", 3/8", 1/2") is easy to bend if you have benders made for stainless! Same thing goes for tubing cutters, etc. Have to be made for stainless, or you're beating your head against a wall.