Maybe I've got too much time on my hands.
Body: 7
Armor: 8
Cargo: 65
Handling: 5
AutoNav: 2
Sensor: 4
Seating: 2+8b
Entry: 4d
Load: 1,671
Speed: 186
Accel.: 20
Sig.: 0
Fuel: 1,840l Jet
Econ.: 0.25km/l
Chassis: Cargo Helicopter
S.I.: Lots
Avail.: 32/32d
Cost: 945,500
MIL Mi-24D/Hind-DOther features: APPS (Pilot&Gunner), Contingency Maneuver Controls-1, Crash Cages, ECM-1, Electronic Ports, Enviroseal (Gas&Overpressure), Folding Bench Seats, Launch Control Systems (3 Medium), Life Support (10 man-hrs), Power Amplifiers-4, Rocket/Missile Mounts (4 External Standard), Roll Bars, Secondary Controls, Turret (Small Remote, Gunnery Recoil Adjuster-7, YaKB-12.7/Vanquisher HMG, Ammo Bin for 1,470 HMG rounds).
This is true to form in top speed, ammo amounts and fuel amount/range. There are only 4 rocket/missile mounts because 1,200kg is about as much as the 6 mounts on the actual Hind can carry. Things such as ECM, Sensors, Power Amps, etc are just thrown in there based on the descriptions (you could get rid of the Power Amps altogether).
The Load could easily be 1,000kg higher (the chassis can handle it, it's 250 nuyen to the cost per 10kg extra load), and the Cargo should be put at anything you think would fit in the thing (again the chassis has got room, it's 1,250 nuyen per 1CF extra cargo).
A version with the GSh-30K autocannon (use Victory AC in an external hardpoint) is slightly cheaper (33,750 nuyen less) but has less room (4CF less) because of the huge ammo bin. I figured you'd be more interested in the minigun version, the autocannon might be a bit overkill. Also, the mount of the minigun negates any and all recoil from the weapon.
Then just mod it away by adding Rigger Adaptation and better electronics (Sensors, ECM, Power Amps, etc). Don't bother with thermal baffles etc because you can't get the Sig up to a respectable figure anyway -- for the sensors of the 2060s it's a shining beacon whenever it's in the air.
In the black market of the 2060s it would most likely cost a lot less than the price above. It would also be in horribly bad shape, and might not have many of the mentioned parts -- especially weapons and electronics might have been scavenged. Remember: The design is 87 years old in 2063. That's a lot in the world of aviation.
PS. The minigun in question here, the YaKB-12.7 apparently has a cyclic maximum RoF of 4,500rpm, and it's user selectable. On the other hand, the twin-barrell 30mm cannon has a max cyclic RoF of 2,600rpm, which sounds far more scary.