LOL!
I'd go with the tusker, makes me think of oliphants from TLOR
I've seen some of the AI suits built with a chin plate, too, maybe it's the new Kyklops kit. And then, very appropriate, there's a cyclops skull decal in the kit, to decorate the head and plate.
Regarding Walmart and kits, they used to, and I think there might still be some regional differences about carrying kits, but yes, the ones around here dropped them a couple of years ago. I never really went to Walmart for modeling stuff, though I have bought other things there that could be used for our hobby. Walmart used to carry 21st Century Toys/Blue Box vehicles and aircraft, and then gave them up, too.
We're fortunate here in the Lehigh Valley, we have a couple of old-school LHS, plus Hobbytown, Michael's, AC Moore and a HobbyLobby. Combined with Internet sales, we have pretty good access to kits and supplies.