The piece on that site is not a piece of PK, but is most likely a piece of Kralik. Actually, 4 of the pieces on that page attributed to PK are actually not PK production. I would likely attribute your piece to Kralik.
This is also not a piece of Dugan..... for sure.....
I believe the reference to Dugan and Loetz.com was to shape on the right end of the 1st attached image, and the left side of the second image. Pics used with permission....
Craig