.
There's a few here but none of them are spot on:
http://www.timetunnel-jp.com/IWC_markXV.html
http://cgi.ebay.de/IWC-SCHAFFHAUSEN-MAR ... dZViewItem
http://cgi.ebay.com/IWC-REF-3253-MARK-X ... dZViewItem
From what I can see, it's (very-very) similar to the PRS-53 ... only it's a tad bigger (39mm?) ... the bezel is a tad higher ... the case a tad thinner but the back drops lower ... and the crown a tad bigger and better made.
john