Achtungpanzer.com has some infos on the bulgarian Panthers
Link:
http://www.achtungpanzer.com/articles/bulpanth.htm
And I've found this link:
http://forum.axishistory.com/viewtopic.php?t=92376
with a pic from the french Panthers from the 503ème RCC.
On this pic it seems to me that the gun and the gun mantlet have been repainted in olive drab. But without a colour picture...it's just a speculation.
Regards,