I seem to recall from the dim and distant past that RAFG used chippies to fly along the West/East German border to see what they could see. I can definately remember seeing a picture of one somewhere.
Also, I believe the venerable Bulldog was armed by the Swedish airforce? Also, the Bulldog was built specifically for the military trainer market!!
However, I do laugh when people advertise them as "This genuine warbird....." - they're what alcoholic UAS students used to fly
Is someone angling for a excuse to wear a bonedome whilst flying?