Here is another moonphase watch from the UK site and it also looks like it has a better crown and states it's officially certified. I'm more inclined to believe the one on E-Bay is possibly a fake. Rolex seems to have the trademark of officially certifying their timepieces and this one is not certified which breaks tradition.
http://www.thewatchguru.co.uk/Vintag...ches.asp?pn=12
Finally, here is the last one from the UK site which also has the certification.
http://www.thewatchguru.co.uk/Vintag...ches.asp?pn=13
Terry Newton