I've done some searching, but I can't seem to find any.
Any help -- perhaps a template that adds this ability to standard monsters?
the cleric class template probably does
none that I know of, might have to work with your GM on that. Personally I find all purpose summoning a bit tacky, but you should be able to get close to a fair custom summon by using the oracle class fixed to a creature you can summon at lower level.