Antique / vintage Swedish metal Wax seal stamp / Pipe tamper / Game piece Signed RB Nordic design 1910s 1920s Desktop decor store Collectible gift

I am still not sure what it is :)
I had theories like an old weight or mortar, but the most plausible ones I store have mentioned in the title.
What intrigues me is the fact the piece is signed.
When trying to find the meaning of its shape, i thought it resembles some emblem with a wheel, wings and a royal crown - what if it was made for the state railways or postal service?
Whatever it is, the piece is very special.
8.5 cm tall. Heavy : weight 142 gram.
Nice antique condition with some patina.