DSA, I would buy the whole trigger group so everything starts of new.
It is extremely easy to disassemble the trigger group. Open the reciever, I usually unscrew the two halves to make it less combersome, use a screw driver to pop out the hammer spring assembly at the reciever, turn the saftey lever up and slide out, rotate that sheet metal looking catch to unlock the hammmer/trigger/sear pins from the reciever and slide out. Watch the springs so they don't go flying into never never land.