Due to you mentioning the L vs gal, I'm assuming you're either in Canada or Europe, not the US. (or at least not in the US). I don't know of much outside the US, and shipping from US to there probably isn't cheap... That being said, if you're interested in US ones, and just have made the right conversion to L already and are leaps and bounds ahead of most silly americans (like me), I can find a few different places for you that would probably work in the US, just let me know if I'm in the dark or not
and now I realize due to my lack of good metric knowledge you're looking at smaller sized ones anyway, and I don't know a good supplier for those... sorry!