I got this today. Not exactly pristine, but working and only £5.50. Arctos is a German brand - with some info from Mike Stuffler here: https://forums.watchuseek.com/f11/puw...ers-50390.html
Here it is with a new crystal and strap.
I was expecting an obscure German movement - but it has a clearly marked Eta 1080. see bidfun-db ETA_1080: ETA 1080
It has Incabloc shock protection and a Nivaflex mainspring. Probably mid 50's.
Anyway, not that many Arctoses have been posted in here so there it is.