I would, because I like to, make my own. Some 3/4" or 1" X 1/8" weld able(mild steel)strapping and a couple of cap screws.
Form the strapping to fit around the battery, so that the cell caps are removable and buy two SS 1/4X20 cap screws, cut the heads off and have them welded to the ends of the straps. Drill corresponding holes through the battery box and metal plate below the box and use nylock nuts and washers to tighten.
The strap would wrap around the top and sides in one piece and create a problem of time and tools for a possible thief. I would use SS cap screws, nuts and washers, paint the strap with a corrosion resistant spray paint.
Less than $20 for the metal and $20 for the local muffler shop to weld.