Weet iemand hoe ik de echtheid van onderstaande Omega medicus mechanisch "formwerk" kaliber R17.8SC kan checken?

[Omaragdi]

[hoefnix]

http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&&2uswk&Omega_R17_8SC

http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&0&2uswk&Omega_300

[hoefnix]

https://omegaforums.net/threads/omega-2300-1-with-cal-r17-8sc.43330/