Hope you're feeling better toothfairy. Standard European bar measures are 25 ml and 35 ml. If you don't have a bar measure or jigger and why would you if you don't make cocktails you could use a tablespoon. 2 tablespoons = 30 ml, so kind of half way in between. A half-full eggcup is about the same. As long as you measure all the ingredients with the same measure, the mix will work.
The plane is waiting but I have to hoover, dust and clean ! WHY ???
Steve Wright in the Afternoon.