Benelli Supernova extensions should work with some minor modification. Don't know of any extensions made specifically for this gun though.

Just my opinion but if you are going to use the gun a lot go with a know brand like benelli, beretta ,mossberg or remington where you can get the correct aftermarket parts and have support 5-10 years down the road when you need replacement parts. I have a shotgun in my safe that I have been looking for a replacement for a bad magazine tube and I have not been able to get one in 4 years now By the way it is a S&W shotgun that was made in the 1980s

Just my opinion but if you are going to use the gun a lot go with a know brand like benelli, beretta ,mossberg or remington where you can get the correct aftermarket parts and have support 5-10 years down the road when you need replacement parts. I have
a shotgun in my safe that I have been looking for a replacement for a bad magazine tube and I have not been able to get one in 4 years now By the way it is a S&W shotgun that was made in the 1980s

Christopher, the 2nd reviewer here used this Carlson's Benelli Nova/Super Nova - 7-Shot Magazine Extension. He had to remove a quarter inch of tube length but it worked great (picture with it installed also) : joeboboutfitters.com/Carlson-s-Benelli-Nova-Super-Nova-7-Shot-04502-p/car-04502.htm