To get the cc's I use a cheap CD case covers with a small drilled hole and 10ML syringe to inject oil, simply count the cc's until you can see the chambers are full of oil (any oil is good).

You may need to seal around the chambers with some coloured (marine?) grease just to make it easy to see when it is full and to make sure no oil leaks out.

I think I need 21cc+ chambers to put me back onto pump fuel.

EDIT: Oh, could you also confirm if the ports are standard or larger?