I think all the stocks are compatible. The SBE stock seems to be the same thing on the Benelli Practicals (10 round M1S90s).
Only difference, methinks, from the M1S90 'Tactical' stock is the sling loop on the sides instead of the stud on the bottom. Because of the sling loops on the side, the recoil reducer, if you have one, for your SBE won't fit in there.
The pistol grips and 'tactical' rifle grip stock are listed as M1 and M3 because they 'just ain't right' for the SBE...and the untactical ones are listed for the SBE and M1 Field, but I think they take the same stock.
Heck you could probably put an M4 Super 90 collapsible stock on your SBE if you got a hold of one.
