I am in the process of putting my 310B backhoe back together. I only found some mastic and traces of the pads when I took things apart. I figure they help with vibration and rattles so I would like to replace them. They are items #4 in left drawing and #6 and 7 in the right drawing. I am thinking of using either black sponge rubber weatherstrip (3/8" thick X 1" wide) or black rubber garage weather strip (1" thick X 2" wide) and modifying as needed. Without anything to compare to, are the materials comparable? Anyone have some dimensions, especially thicknesses?
I would say you need something like "solid" rubber rather than "sponge" rubber, if you get my drift. If you have any outfit close to you that sells water pumping equipment & parts see if you find some rubber insertion material. It comes in sheets and you can cut it to whatever profile. Failing that a bit of old conveyor belting maybe ..?