Another sculptor/model maker here
There was an Abe statue produced some years ago, with no notice given to OWI. They requested the company cease production as they were infringing their IP. Fair enough!
There were also talks of official merchandise with a company going so far as to produce prototypes, including Abe figures and Molluck masks, etc. can't remember the thread but we discussed some photos here on the forums. I guess it didn't pan out
If you obtained permission, it'd be fine. I've been curious for a while what the legal situation is exactly regarding sale of fan artwork. Many comic book artists sell commissions of copyrighted/trademarked characters in their spare time, and don't seem to have any problems doing so.
I would love an Abe statue (made a couple myself in the past, could do much better now but would buy one immediately if it went on sale!) That said, I'm only really interested if something's official. For me I guess it's just a quality/accuracy assurance thing. Even if I made one myself as accurate as possible, it still wouldn't feel quite right somehow without that final seal of approval.