totally the wrong forum, but if he uses a shocker, im sure he's set. I've shot many types of markers, and most players use a specific type for certain reasons. I habe an angel, 2 autockers, a bushmaster, and a new Evil Oman. Of them all, I'd give positive words about all of them...
Currently, I'm stuck on this Evil Oman which is a great marker for the money ($roughly 400). It will match my angel for speed, and is fairly accurate. It isn't quite as accurate as my autococker, but I have a ton of money into the cocker.
Maybe the best thing to buy your guy would be a nice high pressure bottle, that he can pack full of CO2 to get the most shots out of his shocker.
You could also go with a new barrel system (evil pipe, or Freak! set), new mask, gloves, shoes, pants, etc. Paintball is expensive, sometimes I regret how much money I have dumped into it. Luckily once you start winning tournements, items start to flow in for a minimal cost.