Oval ink caps? Does anyone make them?

I like mixing and tinting between a lot of different colors when I tattoo. I might not even use some of them, I might only use a little bit, and I'll pour many caps of white to keep it clean. If I know I'm using a lot of a color and don't care about it being contaminated, like black, I will pour it in bigger ink caps, like a #16. For everything else I'll use #9 caps or even smaller for white, ext.. The #9s are great because they hold a good amount of ink but not too much that I'm wasting it. So I can pour a lot of colors. And a 15 mag will fit in them. But I just started using hawk cartriges (loving it) ..and I'm using the bigger mags, but I can't use them in the 9#s, I have to pour all this ink in the #16s. It's gonna run me dry!! So yeah.. someone's gotta make some oval or elliptical or rectangular or parallelogramical.. ink caps. I think it would be good.. What do you know? What do you think?

Incase that wasn't clear.. the ovals could fit a big mag while holding less ink and be deep enough to not bang up the needles on the bottom.