Having the dealer do the timing belt will probably be costly, even with the kit from Courtesy Nissan. There's a lot of labor involved (lots of pulleys and brakets to remove to get to the timing chain cover) to get to the timing belt and the dealer will probably charge you an arm and a leg. Depending on the dealer, they may give you a hard time using your own parts.

You might be better off looking for a reputable mechanic, it probably won't cost as much.

-Michael