A833 identification!

Hi guys,

* *can anybody help me to identify my A833 OD i bought in Germany a few days ago?

Here is the picture of casting on main case. I saw on internet that it should be PP833 and after that 4 digits that represent year, but mine is not like that as you can see. Is this maybe 11.04.1986. if there were A833 that year? :)






Thanks in advance.
Author: shone190