It's pretty rare, and that's a cheap price, given how it's in the box with the manual.
I'd say take it, if only because it'll become even more valuable in 10 years.
edit: and rarity guide says that the game, complete in the box, typically goes for $80.
edit 2: http://www.rarityguide.com/n64_view.php?SortDirection=desc&SortField=5&recordsPerPage=20
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The Hunger Games>Mockingjay>Catching Fire
Majora's Mask won GotD. Deal with it.