You are very clearly selling models that are described as Primarchs from the 40k universe and very likely without the permission of the Intellectual property owner (GW).That alone would be a breach of some copy right or another.
As commented on other members some of the models you are looking at selling appear to be copies from other manufactures and the base materials differ from those original models (metal to Plastic). That is a BIG warning sign that these are recast copies (fakes).
TBH most people would not care to much about this as they are just more interested in getting a decent model for a good price irrespective of the origin.
Your main issue here is trust, its obvious that some of the models you wish to sell are not original works where as some maybe, but ether way you cut it you are breaking 1 law or another in the purposeful selling and distribution of these items weather that be illegal copying or copyright infringement.
As to the fact of the importation of these models, Bits is correct if customs end up not liking them then the purchaser is taking on a lot of responsibility.
This contradicts the story of the limited edition story as who ever heard of company creating limited models when they themselves don’t own any of the legal rights to production. And the sale of only 200 would yield no real profits for a company
The fact is this does sound shifty, there are either 1000’s of these being made illegally or you are correct in limited capacity but on the basis that the first model would be a lure.
But the biggest warning sign to me is that you are trying to sell these though a forum site and not a regular sale site. Selling on these sites is usual between players but not for a retailer/manufacturer