When Rickenbacker reintroduced the trapeze tailpiece in 1964 (think: George Harrison's first 360/12) they had to reengineer the bracket to handle the additional pull of the extra 6 strings.  Not only did they upgrade the material to stronger stainless, they made the bracket a bit smaller as well.  That first crack lasted about 15 minutes, then they redesigned it again to the bracket they still use today.  This is a copy of that short-lived bracket: note that the strap bolt hole is closer to the bottom than in the contemporary piece.
 
Hole pattern notwithstanding, it's compatible with all the trapeze tailpieces that we sell (6-string, 12-string, long, bass, etc.).

And yes, the mounting screws are included.