Steel chainring bolts for 11 speed ultra torque?

bondurant

Do these exist? I've stripped one of the Campag alloy bolts on my ultra torque chainset, because they are made of cheese, and would like to replace them with stainless steel bolts if possible. If they don't, does anyone know where I am likely to be able to buy single replacement Campag bolts?

Thanks in advance for any guidance