Freezer,
I hope that you are not contemplating turning a Handi Rifle into a pistol. That would be a sure way to get to meet a lot of the ATF's finest and to get an all expense paid stay at Club Fed. The gun is sold as a rifle and you can't legally change it into a handgun. As far as NEF making a single shot pistol, I have not heard of any talk about this but it would be sort of cool if they would consider it.
Best,
Wolfgang