Woodstock HP2x replacement feet needed

[calc-calcs]

Original rubber feet are about 5.5mm x 8.2mm and overall 7mm deep including the dimple on the internal face.

Another idea would be to use a cutout of black anti-static foam the kind used to protect ICs. There is one variety that is rather stiff but still has enough springiness to allow for a tight fit, and the material is easily cut to shape. It would also be more wear resistant than the eraser cutout substitute.