Try and find a proper greengrocer mate, they normally sell pickling vinny by the half gallon, and it already has a bit of flavouring in it, just add your own spices to your taste. I generally add a heaped teaspoon of sugar as well.
What ever you do, do not use the stuff that comes in plastic cans. It is not vinegar, it's Non brewed condiment which is synthetic vinegar and does not have the properties of spirit or malt vinegar.
https://en.wikipedia.org/wiki/Non-brewed_condiment
TC