Hello!
Of the exporting historical artifacts from Estonia. The Estonian authority to contact for permissions is
Muinsuskaitseamet ( The National Heritage Board). They have homepage in English too:
http://www.muinas.ee/index_eng.html
I am pretty sure the Ju 88 fin affair should be negotiable also after the fact. I fully understand people bying such artifacts to fulfill own interests and passion (even without any permissions) but not if the intent is to make money.
Arensberg is German for Kuressaare. Kuressaare is the biggest town in Saaremaa island. Saaremaa is in other (=indo-European) languages Ösel, Osel etc. Soviet era maps show Kuressaare with name Kingissepp.
Regards,
Kari