I need help with buying these converses?

Ok, so I want these converses right here: here’s the link

http://www.ebay.com/itm/Chuck-Taylor-Con…

The only problem is that they’re all in mens, not womens. I’m a girl and I have a pair of regular converses that are size 6, and here’s the listing for these ones:

Mens 4 = Womens 6

Mens 5 = Womens 7

Mens 6 = Womens 8

Now the one I would get is the first one, “Mens 4 = women’s 6” but they don’t have this option anymore, so now I’m forced to go with the second one, which would be size 7 in womens. The size would be one up higher than my original but I wanted to know if it would be way bigger or just a little bigger…should I take the chance and just go with the size 7 one?? I don’t want to waste almost $70 here.