There are many radical initiators that can substitute it, practicaly any compound with the -CO-OO-CO- group will do, probably AIBN or other aza compounds would work as well. And quite probably a mercury lamp would suffice too. But as far as I know, peroxybenzoic acid anhydride (aka "benzoyl peroxide") is the only one that you can easily get OTC, so I can see no point in your question. Or are you perhaps interested in other radical initiators that might increase the yields?