Don't know where you live, but I'd suggest checking at a Cabela's, Gander Mountain, or Bass Pro Shop. I was in Minnesota and stopped at the Cabela's off of I-35. Picked up an aluminum sided double gun case for $99 in the bargain cave, half the price of the case new. Only problem with it was a scratch in the side. My brother did the same thing and picked up a case at the Sidney, NE store, bit "fancier" model, paid $125. Both cases went to Africa and Alaska and can take the affects of traveling.
You should be able to find several in the price range you mentioned, so good luck in your search.
Snake