I would definitely go with the gift card to the local skate shop, or at least that's what I would like best. That is the best place to buy boards, and this way he can choose what he wants himself. If he currently skates, then I would say 50-75 dollars is probably good, will get him at least a new deck. The rest of the board can usually be used for a while, its the deck that wears out or breaks first.
Complete skateboard costs $150
Skateboard deck costs $30 to $50
Skateboard wheels costs $30
Skateboard trucks cost $50
Skateboard bearings cost $15 to $80 ($30 on average)
Hope that helps, I would say $50+ is good
If he already skates he probably has trucks and wheels, so all you'd need to get him is a deck and they usually run around 35-50 dollars. If he doesn't have wheels bearings and trucks that will cost about another 50 dollars.
220. Get him a complete
Yoooo sounds like something is dying outside my house. Stupid cats.