It's not as big as Costco, but with a few acres inside devoted to sporting goods, Sports Authority http://www.sportsauthority.com/ definitely has a better selection. If you're looking for something obscure, it's best to start someplace big enough to have a little of everything. It's also a good place to browse, to see the newer versions of things I used as a kid. The don't waste their time of many of the low-quality, cheap versions of things found in more mainstream department stores, which is to their credit.
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