Agreed. There is little barrier to obtaining any item you want, other than price. The issue is a lot of buyers really want an item, but do not want to prepay. Try ordering from any retailer stateside, somthing that is obscure and not very popular and see if they arn't going to ask for a prepayment.
As for prices, most retailers buy their products amd pay retail price for them
A $300.00 AEG X1.9% (state taxes) = $327.00 X exchange rate 1.22% = $398.94, not to mention shipping it up, and shipping to the buyer (another $50.00) So $450.00 without one cent of profit.
As for metal bodies, they are just as difficult to get as the complete item. I have found then actully more difficult to import, as an airsoft gun is obviously a toy, but a metal receiver looks just like a real firearm receiver especially of it has no mech box.