Doesn't work either - either bosons exist, and are plentiful, or there are none of them. Being rarer than one is either not special, or impossible!
Due to a phenomenon known as color confinement, quarks are never directly observed or found in isolation; they can only be found within hadrons
You want free quark, or if you want obscure-physics cred, you could say 'rarer than an odderon'. The (non?)existence of odderons has been an argument in particle physics for about 30 years...