No idea what the mesh is but moononsun seems to have removed all of his creations from everywhere but
Sims Crossing. On his MTS profile he requests that his clothing meshes not be reuploaded anywhere. So you may just need to PM him at Sims Crossing and hope for the best because he hasn't been active since August last year. Because of his policy, it is unlikely that you will find his meshes anywhere and they cannot be re-uploaded here, so you just need to try your luck contacting him directly or through the Sims Crossing site administrator if he doesn't reply in a long time (eg. a fornight or longer, NOT a couple of hours or days; not everyone is logged in around the clock and every day).