Most fancy dress catalogues feature cave girl outfits. With very few exceptions they tend to feature animal prints rather than the One Million Years BC fur-deerskin approach. No doubt because it's considerably cheaper to print leopard spots on any old polyester. A surprising number of these photos feature girls holding large bones. I can't think what sort of symbolism they are after here!
The one with the fishnet tights isn't even trying to be a cavegirl and really only the plain brown one is anywhere near "authentic". I suspect that the only time a decent looking girls wears any of these outfits is when they are the models being photographed for these pictures. The thought of some of these get ups on the average woman is terrifying to imagine!