what are some jungle runes for an ap like nunu or amumu?

movement speed quints
Magic Pen Red
Armow yellow, MR blue.

GG have fun

I don't run MPen on any of my junglers, simply because it doesn't really help their initial clear, and that's the biggest goal of runes for a jungle champ.

I have several rune pages that I use for jungling, with variations of ArPen or AS reds; AP/level or MR/level blues; MS, LS, or even Gp/10 quints; but always flat armor yellows.

Edit: I also have an additional set of runes with a mix of flat AD and crit damage reds and crit damage quints that I use for GP. Flat ADs are cheap and also useful on a jungler, although I prefer ArPen on the majority of my (non attack speed) jungle pages.