Do you want the Tee shape or triangle shape? 1/8" thick or 3/16ths? Do you want one with lead outs or no lead outs? I'm asking because I could make one for you. I have a few 4" made. I'll post some pics if you're interested.

MM

Pic is of 3 proto types for sub 600 planes 4 x 11/16. Lower right was final design and I have them in several planes. Full size would be slightly larger and 4 x 7/8 or custom order.