Used solid rollers

Don't try and run any of them without rebuilding ALL of them. It isn't worth the risk. Better yet, check into the cams you want to run, and be sure the roller diameter and cam profile are meant for each other. The best course of action though in my opinion is buy new ones. The valve train is not a place to try and save money. The proper springs, cam design, rockers, and pushrods all need to match each other. If the quality of any of those parts is not up to the task, the least of your problems will be a sag in the power curve. The worst will be catastrophic engine failure.