Yes, but you'd be better off changing to a different style of handguard with rails to let you attach a torch more easily. Try not to confuse "upgrade" with "accessorise" though, "upgrade" is generally taken as changing the internals to achieve better performance (which to be honest you shouldn't need for a while yet) whereas the bits you bolt on to change the look are more "accessories" - stocks, handguards, sights etc.
You WILL ask loads of questions on what to get (Flex will advise you to buy everything the same as he did but that's just his way and we love him for it - kinda like a little puppy), you WILL spunk a load of cash on stuff to bolt onto your gun to make it "yours" and you WILL end up with most if not all of it skulking around on your bedroom floor when you realise it eith doesn't help, doesn't fit or makes your gun too heavy to bother with. Don't feel bad about it though, everyone does it. It's like an airsoft rite of passage if you will.
This is the handguard with built in torch http://www.wgcshop.com/wgc2008/main/product_detail1.php?search_From=searchItem&item=GP-ACC-726A&search=special&rs=m500&catid=&cat=&view_choice=a
or you could get a Magpul MOE style handguard but you'll also need the rail kit to be able to bolt torches on. Failing that you can look for a 7" RIS handguard.