Hello everyone. Im new here and not real familiar with the Colt Trooper mk iii but i just inherited one from my father. The gun is a 1980 model and has had less than a box of shells fired through it but it does have an issue with it. The latch will not move and it will not keep the cylinder locked closed. Im really wanting to get it fixed and dont have any idea how expensive it will be and dont even know who to get to do it, or do i have to have it done through Colt themselves? Any help here would really be appreciated. Thanks.