Just a short update. My local gunsmith said he contacted First Jack for a cylinder stop and he didn't have one for this gun.
Also, with the top broke open, when I pull the trigger you can see the cylinder stop moving up and down but it never clears the floor of the frame enough to make contact with the cylinder. Visually the end doesn't look worn, but I could be wrong. So, there seems to be something wrong with the cylinder stop (bent, worn, broken) or with another part (spring?) that pushes the cylinder stop up. I took the side plate off and can't really tell anything since I'm a newbie. I still want to pursue fixing it, but I'm not 100% sure a cylinder stop will fix it. I'll let you know if I get any further. tlay, let me know when you are back. Thanks everyone.