Denes,

My guess would be that this is a Polish LWS-2,
The last letter is not clear, however i believe that "PCK" is visible on the upper left wing tip. "PCK" would be short for Polski Czerwony Krzyz (Polish Red Cross).

http://www.samolotypolskie.pl/samoloty/1728/126/LWS-2

The above link mentions that the prototype was capture by the Germans in 1939, and its furture loses are unkown. Germans may have given it to the Rumanians, or it may have been evacuaded by the Poles to Rumania... Just guessing.

Hope this helps,
Aleksander