A lot of the eBay sold BIN auctions having them go from $15-25, depending on how many it holds. For a BIN for 11 games (which is what yours looks like it holds), I'd go with the lower end of that, maybe $17. Auctions come in a little lower.
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My NES cartridge collection: 208/768 (27.08%)
Just got a 3DS - looking to start a DS/3DS collection. If you have any games you'd like to part with (preferably with case), PM me.