If you have a CC syringe you can level your head and use water with a drop of Dawn soap (to break surface tension) and you can measure it good enough for stock.
I made most of mine with tape, compass, drill and a jigsaw, you want at least 1/8" clear plastic. They'll look at you funny but most pharmacy's will give you a syringe, you want the biggest they have. I've always used water with a drop of soap, because most oils, chemicals, etc., will wreck the rubber piston of the syringe plunger.
I used to have a 50cc syringe, it was boss, but it wore out. Had a glass graduated burette, busted that shit.
Just CCed a pair of heads with a 3cc syringe what a PITA, I need a new syringe.