Go here to get the manual and parts breakdown to see what I am talking about.
http://www.spyder.tv/section/support...er_xtra_07.pdf
In the diagram you will see that the sear is held in by a pin(RPN005). You have to remove this pin. Before you do examine bothsides of the pin. One side will not be round, it will be like a multi point star. When you remove the pin you must drive it out with a hammer and pin punch from the ROUND SIDE ONLY!!!! This will release the sear from the body. Now if the spring is broken part of it will come out with the sear. The other part of the spring will be held in by a second pin(RPN006). Remove it as you did the first on,driving it out with a hammer an punch from the ROUND SIDE OF THE PIN ONLY!!!!! This will free up the second half of the broken spring. Install all the new parts and replace the pins in the reverse order you took them out. If this is Over your skill level take it to a Paintball Air smith/tech and have them do it. If you do try to fix it yourself I take no responsiblity for any damage you do to your marker.
Good Luck. If you have any questions PM me and I will try to help you out.