Also, consider looking for a deal on a lightly used smoker on craigslist or your local paper... you may be able to score a $400+ dollar smoker in great shape and still stay within your budget... a Weber Smokey Mountain is the one I would suggest looking for!
Weber smokey mountain will cost you more than that, but it is worth it. most of the Horizontal offsets you find at the chain stores are not worth the money and he will loose interest fast if it is his first one, Look for a used WSM online in your area
Sew213 aren't you a sweetheart for getting your BF a smoker! Does he currently have a charcoal or gas grill? Does he have a Weber Kettle? Fill us in a little on his backyard grilling experience. And welcome to the forum BTW!
If you know you "love" charcoal smoking, then you can ignore the ecb. A mini WSM will be under your limit (including the tamale pot and everything), but you'll have to do some handy mods if you're handy. I hate to say this but I would suggest the WSM 14.5, It will cost you 200.00 thou, but those will be the sweetest 25.00 over budget you'll do ever.