Must say im a little supprised you said mudgaurd came from a Enfield but it did come with a load of Efield parts thanks on that.
It's possibly from a Crusader or Meteor model?
Crusader:http://www.vintagead.com/catalog/store_images/pictures/mcr5636.jpg
I'm not sure if the two stays shown attached to the mudguard are original?
Possibly??
There seems to have been many different styles of mudguard used around that period by Royal Enfield.