I had my hopes up too...The only reason they have "blasters" at Star Tours is because they're obviously fictional and even then they don't have a huge presence.
Avatar however has a huge focus on the weapons and destruction caused by the humans. Disney will never allow realistic depictions of these types of arms.
I suspect there will be big robot suits here and there and plenty of natives with spears if anything at all.
Don't look for this in the gift shop...