I think i read somewhere that a CE lancer Lancer one will fit, but are you sure its the sender unit?
Who told you it was the sender? Could be bad connection/faulty circuit/faulty gauge.
Check your gauge by grounding the sender connection wire(s) at the fuel sender, depends if you have a low fuel light/but one wire is earth, one is switched to earth for the low level light (on or off) may as welll check both if you have the light as well
You could also check the resistance specs of the winding's on the fuel sender, resistance specs should be somewhere in the W/Shop manual, just remember the Ohms resistance will change as the float moves up and down.
WARNING: These specs may not be correct for your model, i think these are CC carby model specs, but not 100% sure, just check with the workshop manual for your cars exact specs, in the meantime this should indicate whether its the sender or gauge that is faulty!