I went through a "consolidation" phase about 6-7 years ago also. Now I am literally considering buying a .357 lever gun as well, and getting it threaded for my 9Osprey w/ .38specials. It's would be a fun, lower cost (comparatively) way to shoot vs my ARs. But I can't bring myself to sell any of my ARs, because I love them. For now, I will lust after that .357 lever gun, and hope I don't bump into one at my LGS, as I need to just save my money right now overall.
Out of curiousity, what casting equipment did you get? I have a 300 BO 220grn sub bullet mold, but I have yet to get a furnace or any lead to use it. Similarly, I would have to buy gas checks, and probably not shoot those lead loads through my silencer, rendering the mold almost moot.
It's hard to make a recommendation on selling an AR if we don't know how many/which ones you have, that would make sense to then sell in place of the lever gun. But if you feel you have two similar ARs, that essentially do the same thing, then I would sell one to buy the lever gun. All of my ARs are very different, so I don't see myself selling one.
Good luck either way! I don't think I really offered any useful thoughts here though!