There's what appears to be a Rockwell 690A or B ( with long range tanks ) based in Antwerp, as recently as last year. Maybe one of the final 6 with the last engine upgrade?
If this aircraft operates under a JAA AOC of some sort, maybe you could call the owners, and see if they might point you in the right direction. It is
00-GOA ( CN 1173 ), and is easy to find via Google, or similar. Even if it's privately operated, the owner is bound to know something useful.
I should point out that I have never had anything to do with the Commander series, but rather wish I had.