Look in the Surplus Military Rifles forum on the EE.
Sportered rifles tend not to show up there unless they are a bit special.
Most of the Bubba Specials end up in Sporting Rifles, it seems.
You are looking for an SMLE or Rifle Number 1 Mark III or III*: all same thing. It takes the Pattern of 1907 Mark I bayonet, BTW.
Put them together and you have the single most brutal-looking crowd-control device ever invented.