Its a 2k dark. The batteries in these things typically go bad so if it doesnt hold a charge its the battery is probably shot. Your options are to hunt for a replacement battery (expensive and possible another bad one), the cr123 mod (youll have to search for that one), or the pmr board mod (PMR BOARD MOD
Yes this is the type that was pumped. Just slot the breech so the bolt stem goes into the other tube (battery tube). Pull the plug out of the battery tube side in the front of the gun and adapt a pump kit to thread into there. Build the linkage to the pump.
The pmr board mod is the way to go as far as electronics. the solenoid plugs right in and you can run a 9v in the frame eliminating the battery.
Body is 2k dark. CCM feed neck, twisted VRA, and dye single frame. the frame is somewhat rare, you dont see them to often. dont know on the barrel