Uxbridge walmart had about three cases of wave one, but no alley vipers. 3 cobra commanders, and i think all the rest. Just no alley vipers. Also only a couple wave 1 vehicles on the shelf.
I have not seen wave 2 vehicles in my travels, but usually there is at least a few wave 1 vehicles with little to no room for a restock yet. So wave 2 vehicles might not come for a little while, at least in my neighbourhood. If wave 1 vehicle stock is any indication, there will be no problem with wave 2.