Tiny pankouping?

[Isaac1998]

I am curious to see what people say about this little piece- it has consistently divided opinion among people who have seen it here, though it is certainly old.

I got it in Eastern Gansu a few months ago, and am pretty sure it is Northern (poss. Shaanxi?)

Dating has been a nightmare- everything from Jin (晋, not 金）to Yuan has been suggested. It's extremely finely made, quite light, and the glaze does appear to resemble earlier Jin pieces, but the lobed shape is more typical of Song or later. Having said that, however, it has a plate-type rim which again suggests it might be earlier in the form of a pankouping. I also feel that the way the glaze has worn & aged is more typical of really ancient pieces, but perhaps it's just had a rough life. 

Suggestions?