Spoke with Omega AUS office and the ASC, and the gen 2200.50.00 I've been looking at checks out.
It's a 2011 make with the 2500D movement.
Full service by OMEGA SC within the past 12 months: New Barrel complete with mainspring, new auto reverser wheel, ratchet wheel, intermediate ratchet wheel, new winding stem. Plus full overhaul of crown, tube, HE valve, crystal assy, bezel, assy, with new spring bars and new hand set fitted, and no polishing required.
Great price and well respected seller, too. Looks like it's happening.
Hope to bombard everyone with some big brother/little brother PO pics in the near future.