Consider This: Benny Gold Standard Raw Denim, $100
While there's plenty of selvage denim to be had under $100, what sets Benny Gold's apart is that it's made in the U.S. from rugged 13.5 oz. denim. At that weight, they're good for all seasons, although you'll definitely need to break them in long before summer comes. A good pair of jeans will last you a long time if you treat them well, and at this price, they'll prove to be more than worth it.