1987 Mitsubishi Mighty Max 2.0.

I need an egr valve. The diaphragm on mine is shot. New replacements are $200 and up. I haven't found a serviceable one in any of the local Pick-a-Part yards. I have already searched and x-referenced part numbers without success but are any of you aware of an affordable egr from any other vehicle that will fit, unofficially?

Thank you in advance.