Best website I know for these lists your model as the 456/1, while I have the next smaller model which is listed as a 456/0, as seen here:
http://johno.myiglou.com/falk.html
The number cast into the base may not be the actual model number, but perhaps only the casting pattern number.
Here's my little gem:
(Attachment Link)
It came to me with a plastic sight "glass" that was badly deformed, a missing blow-down valve handle, and without the original burner. Other than those issues and some flaking paint, she's a beauty and runs really well. Gas burners give throttle capability that the steam line lacks, so if you don't like your mushroom burner, go to gas.
That is a beauty Stoker, the piston/cylinder appears to be the same as mine but looks larger on a slightly smaller boiler. Your exhaust pipe is as it should be, pointing up. I just wish more engines had am adjustable steam valve.