All I can find is that it may be a prototype Syrena W of 1955. If this isn't it, please unlock, as I can't understand Polish, so my investigations are severely limited!
It's a prototype Syrena, but I don't recognise the 'W' designation.
I'll just settle for the year: not 1955!
My computer has a button you click on when you Google on to a foreign language page that says 'TRANSLATE'; click it and Hey Presto! I can read Polish! Maybe you don't have it?