Unspecified Polish or Bohemian brakteat

Hello, I need to help determine the brakteat in the picture. It shows half the circle and half the eagle. It is very similar to the urban emblem of the Polish city of Ratibor. It's just mirror-inverted. The eagle is on the brakteate on right side and on the city emblem is on left side. A very similar brakteat was minted in the Polish city Opole. Just on left side is half-cross. According to one of my Czech colleagues, it is an undetermined coin of one of the Premyslids of Opava (Troppau). I would like to ask the Polish experts for the assessment of the coin.

similar:
http://herbison.com/someoldcoins.org/saur/g/s011.htm
http://herbison.com/someoldcoins.org/saur/g/r074.htm

Only one similar I found, was unfortunately this one from Opole. I have no idea what it could be

I managed to find out from my colleague Pavel Strakoš further information:

On First the coin was found during the 1960s during excavations at the ruins of Cvilin (Lobenstein, Schellenburg) Castle near the Czech town of Krnov (Jägerndorf). The research was carried out by Mrs. Vlasta Šikulová from the Silesian Museum in Opava (Troppau). The coin has never been published in any of its works, it is only kept in the Silesian Museum in Opava.
This information was given to a colleague by the Polish numismatist professor Boris Paskiewic, who further added: "In my opinion, it is not a sign of the city, but two elements of the coat of arms of the Opava Premyslids and the whole is to emulate Opole pennies. I think they come from the years 1460-1470."

More info is not yet :(


Coin of my colleague