Hi
On the auction lister captions it as
P7606, PR-O or PL-O
29 Aug. Spitfire II P7606 (PK-O) F/Lt B. Mickiewicz (POW) Circus 85. Shot down by a Bf109 over Hazebrouck.
from the excellent website
http://www.polishsquadronsremembered.com/
which has a photo of the other side after recovery in a yard.
Cheers
Jerry