Bit of an update:
It arrived while I was on holiday. Packaged extremely well. Box in nice condition, and comparing it to my other 2 spare lamps* it looks clean and new, but has a couple of slight smear marks on the outer bulb.
I'm a pro-audio guy (rather than lighting) but I do know some things about lighting, not enough to be a danger to others though. These lamps look similar to MSD type which are from memory mercury discharge something something something 250w, obviously this is a much lower power one though. For the MSD types, a quick whack of power creates an arc with the tiny bit of mercury and vapour and all that, then the inner bulb heats up and gets brighter. The outer bulb protects it all, but any grease marks can cause hotspots and cause the lamp to blow. Usually, you can't easily tell the age by looking at it, although the mercury will be spattered around in the inner bulb and the glass may be slightly misted. This one looks good, and the anode/cathode and bits in the inner bulb all look nice and clean.
In summary then - Winning! It's good, someone buy the other one before I do!
*Yes, I have 2 complete working Wotan 50 units and 3 additional spare lamps for them. I love these safelights, I also really enjoy being able to read a newspaper in my darkroom, or something!