Era Report: 2750 talks about the Gunslinger Program (originally known as the "Advanced Combat and Maneuvering Skills" Program) but doesn't give us any AToW Stats for it. My stab at it is below, and it'll be added to the next version of my character creation spreadsheet (marked as fan material, of course). Gunslingers were supposed to be legendary, so I ran with that idea.
GUNSLINGER PROGRAM
In 2682, in response to losses from duels with Draconis Combine MechWarriors, the SLDF started the Advanced Combat and Maneuvering Skills program. It's better known by its later name: "Gunslinger". The program was an intense 1-year training regimen backed by an extremely selective screening process that ran through the end of the Star League. Overall, the program achieved a forty-seven percent win rate against the so-called Ronin of the Combine.
Gunslinger Program (600 XP + Field Costs)
Prerequisites: [Attributes] DEX 5+, RFL 5+; [Traits] Good Vision; [Skills] Gunnery/'Mech 5+, Piloting/'Mech 5+; Must have taken Tour of Duty: Star League Defense Force module.
Automatic: [Attributes] RFL (+50 XP), DEX (+50 XP); [Traits] Combat Sense (+100 XP), Enemy (-200 XP), In For Life (-100 XP), Rank (+200 XP); [Special Pilot Abilities] Sniper (+150 XP), Maneuvering Ace (+100 XP); [Skills] Acting (+50 XP), Negotiation (+50 XP), Protocol/Draconis Combine (+50 XP); [Flexible XP] +100
Field
Basic (+1 year): Gunslinger
Military Skill Field
Gunslinger
Requires: MechWarrior Field, DEX 5, RFL 5
Gunnery/'Mech
Piloting/'Mech
Protocol/Draconis Combine
Sensor Operations
Tactics/Land