I've never seen the baffle sold individually by Lenovo, only as part of a FRU which usually includes the riser, baffle, and potentially the i350 card itself (which I list in the original post), and I can't find it by itself in the parts list either. This is one of the reasons I suggested in the post that you buy through Taobao, because there you do seem to be able to buy the baffle by itself or as part of a package that includes the riser, a few necessary screws, etc which doesn't seem to be an official Lenovo offering (even though mine came in a Lenovo branded box). There's a link directly to the item via Superbuy in the original post at the start of the thread, the baffle is ~$10 plus shipping there.
01MN875 is definitely not the right item, based on my Googling that looks like the piece that deflects the airflow at the front of the case. 5M10U50350 is what
@tinfoil3d identified as the M90q baffle (it's also listed in the original post) - which you already have - and
not the right one for the previous gen Tinys, but if you've seen photos of what you're being sent and you're confident it is what you need then maybe they just mislabeled it.