It'd be a fairly difficult task getting SFB specs for a KA ship
Personally, I'd give her similar specs to a C7 (It is a Command Cruiser afterall) and just drop in photons for the front and aft hardpoints.
Just for snorts and warts, the KA spec sheet:
Length: 336 meters
Crew: 350
Marines: 45
Max. Impulse: 1320 k/s
Maneuverability Rating: 0.37/0.24
Mass: 550
Hull Rating: 2.6
Shield Rating: 47.8
Armament:
-Fwd: 2 Disruptors, 2 Torps
-Aft: 2 Disruptors, 1 Torp
-Port and Starboard: 2 Disruptors
Of course these don't exactly convert to SFC specs and I changed the weapons layout on mine to fit more with the K'tinga and SFC's hardpoint setup.