According to Mark Bellomo's "The Ultimate Guide to G.I.JOE 1982-1994" there were 3 types of Bazooka accessories that were released with Zap. Two of them were offered with the straight arm figure, and the other one with the swivel arm version.
The two handle bazooka was offered with the straight arm Bazooka but Hasbro decided to change it because it was breaking two many Zap fingers.
According to the guide and the author, the two handle bazooka variant was once seen sell for 10$.
In my life of joe collecting I have only come accross one in 1 out of 5 bazookas obtained. So yes it is quite hard to find.
