Well done Peter. Looks like we might be closer to getting a little more detail on these things.
 
There are actually part numbers I have found but only on the nylon blocks for the runners. There a three pairs (Left and Right). Attached is a picture showing one of the nylon blocks and the part number. The part number in the picture is KW8973939L and the opposite side block is KW8973940R. This might help identify the exact model sunroof used in the Escorts.
 
Thanks Whooligan for your help as well, much appreciated.
 

 
Cheers,
 
Adil