I'm looking for a Rhino Choke to use with Hevi-Shot, The Nitro Company offers them for 80.00, I have found some Rhino's, on the net for less than 50.00 but not sure which one works best with the Hevi-Shot, I know some of you guys probably shoot the Rhino with Hevi-Shot. The one I have found is a .680 ported choke, is this the one Nitro recommends? Where else might a fellar find the Rhino chokes on the net?