Brian,
As Drew already stated, you may very well indeed have a trap package gun. To note though, the double barrel trap package as a special option was changed in 1925 or so with the advent of the Vent rib option.
It seems as though what was once special order options became more "a la carte" in late 1925 and Hunter Arms advertised these type of guns as TRAP AND FIELD guns. Since your gun has the Vent rib option, it will not have the "T" in the ledger as the "T" was dropped and replaced in the coding, at least I believe this, to REOBV, standing for Regular frame, ejectors, Hunter selective one trigger, Beavertail, Vent rib.
Earlier guns were marked as such with the "T", at least that is the theory. Your guns sounds wonderful...would love to see pictures of it as on a side note, there have been several variations of engraving of the side plates on Specialty grades, thus it would be neat to see both sidelocks in a picture to compare. Drew has a Picture Trail showing the different variations...I don't have the link handy, but I am sure he will supply it if he reads this...he has put alot of work into things like this.