Now that I've seen a clearer pic, it is evident that that is a replacement cowling panel, judging by the 'break' in what I presume is the red nose band. I did find a colour pic of nose art similar to that which you described, but it was on the P47 'Princess Pat'. I think this is the one I was probably thinking of, when I thought the description was familiar.
If you don't have the pic of 'Princess Pat', I'll happily post it, so you can compare with your piece of recovered wreckage.
Cheers,
Terry.