Game Stop may have some games in your price range for him. I have quite a few nephews around that age, and here's what I was told for them: nerf stuff (anything), video games, and soccer stuff. I was told this after I bought them stuff. I had been informed they don't play with toys only video games or movies...so I got them gift cards to Game Stop...and bop-its (I figure they'll play anything that is noisy like that even if it's not a video game) and gift cards to cold stone (game stop where they live is next door to cold stone...so I thought it would be an outing). I saw some soccer jerseys and hats at Ross for $8 and $15 for the older ones of their favortie teams, so I got those for my sister to give them. All that being said you could also get him a movie or something for a favorite team of his if he's into sports.
Or you could get him a football or basketball too...then he has something to do outside weather permitting at your place...there are RAZR scooters too...I think those are around $20 I've gottent hose for the kiddos and they loved them.