How can I store the extras for later?

Generally, pancakes (crepes) last a day in the fridge and about two months in the freezer.
Both with be better if filled just before serving, but you could store a filled crepe in the fridge for a day.
To use the frozen ones, defrost either overnight in fridge or a few minutes in an appliance (toaster oven, microwwave). Then fill with chosen meat, veg and/or cheese.