As noted in the first reply, you can send your item as a First Class package for $5.70 or less depending on the package weight (up to 15.99 ounces) and on where your buyer lives.
The person who posted those prices lives in Hawaii and might have forgotten that all package postage, even First Class, depends on distance. If your package weighs 4 ounces or less, the price range for eBay labels would be $2.74 - $3.18. Set up your listing with calculated shipping based on the actual weight of your packed item.
That $7.65 price that you saw was for Priority Mail, but you can use First Class package.
USPS divides all First Class pieces into 3 categories: letters, flats (AK Large envelopes) and packages. You can't send your game as a letter, because the maximum allowed thickness for a letter is 1/4 inch.
