First of all, if you are actually the father and not the son (we have kids pulling that line all the time) then I would advise you to teach your son some basic firearm handling principles (even though these aren't real they should be treated as such) like NOT BRANDISHING THEM IN PUBLIC! That should be common sense, but nevertheless never have him walk around with it. For everyones sake if not his own.
Second, I would advise you to research any purchases you make, especially when it comes to airsoft. Try and find as much material as you can and eventrually you will be able to differentiate between jackasses who don't know what the fuck their talking about (ex: idiots on youtube "this is the clip......it holds the bbs.......this is the grip......its cool....."etc...) Usually reviews on this website in the Reviews section are handy, same with ArniesAirsoft. Doing so you will find that the SwissArms has TERRIBLE tollerence issues with upgrade/replacement parts as its a clone of the model the parts were designed to fit into. I'd recomend
www.mechbox.com for tutorials for how to (dis)assemble the gun. As for parts
www.airsoftparts.ca should be your first go-to as its based in Canada and saves you the hassle of dealing with the CBSA (Border) and you would be supporting local businesses (this is of course assuming that you are in Canada) Fill out your profile a bit more, like location, so that we can also help send you to someone who has knowledge on these and can show you first hand.