MAF Problem. Please help
 

My sister has a 2003 Eclipse Spyder GT. It gave a MAF code sensor was bad. Put on an aftermarket sensor but still getting code. The mechanic wants us to search junkyards to find an OEM sensor of a wrecked model. This makes no sense to me. I would think replacing with an aftermarket made for the vehicle wouldn't make any difference. It has not on my Explorer which I replaced two years ago. Anybody got any suggestions or similar experiences? I would really appreciate any help I could get. She is an hour and half away and I know nothing about the mechanic she's working with.