here's a pic of the part we're looking for. how this photo would actually aid anyone in finding it is beyond my scope of understanding, but it can't hurt to have a visual i suppose?

the silver, vaguely rectangular thingy is the part itself - the bronze-edged plate attached on the right side of it is just a platform used to attach the pump to the diagnostics at the "lab" (some nice mexican guy's shop).

more pics to follow....