What is the difference between the two? Steve points out fit and finish, and mentions material. Is saving that much money, (I agree, it IS a lot), worth tearing your dash apart again when this fails? I understand this is why you posted this, but think about it: how can they sell the same thing for so much less money?
This is how some of the parts suppliers make cheaper parts. They do not hold the locations of holes and other features to the tight tolerances the OEM does, and the part is faster to produce. We see this in my industry frequently. I am constantly questioned as to why the original parts cost so much. But my field service people are also constantly dealing with repairing machines that have low quality parts bolted to them! I could cut the price in half easily on many of my parts if I would relax the tolerances on them.
My $.02. I always buy the parts I KNOW will fit. I wish you good luck in your repair and have fun!
P.S. Partsshop has two variations of for 1987 300e, evaporator, one for $128 and one for $156, just to add to your confusion!
1989 560SEL (172k)
1989 325IC (122K)
2004 Suzuki Volusia LE (3500 miles)
2005 Yamaha Road Star (20 K miles)