You can always make one. I made mine with a sheet of acrylic I bought at home depot. If you apply heat with a butane torch, the acrylic can be bent into the shape you want. The teeth are then made with a drill and jig saw. Essentially you drill holes for each tooth about an inch from the top and then cut open the top of the hole with a jig saw. Silicone into the corner or back of the tank and good to go. There are some helpful youtube videos. Mine has lasted 9 years.
Yes, I drilled the tank myself and put 2 stand pipes in a corner for a corner overflow. Then I just had to make a sort of obtuse L-shaped weir and connect it to the sides and bottom of the tank to create the “box”. For a rear overflow, you should be able to make a U-shape and connect to the tank similarly.
