I have 1, but have seen very few.
A completed auction search just now on Ebay and GB show no results for a PO-Q.
Neither site has current listing with a PO-Q.

With that it would seem to be they are rare at this time.
I'd guess a value of $50-$65+

Did see where a N marked sight with the blade height number on the outer left ear (S'G') #5 recently sold for $145.00
Hope I didn't Jinx you and someone finds a crate of them tomorrow.

Cheers,
Charlie-Painter777