Welcome to the Troika Cafe, Richard. Unfortunately, I don't have the storage capacity to allow uploading of images. If you have access to any of the free image hosting sites, such as Flikr, you can embed a BBCode link to the image file. I host my images on SmugMug and embed links from that site to the Troika Cafe.
I have never seen anything from Iain Draper. The only reference to him that I recall at the bottom of the
Digital Museum of Cornish Ceramics - Troika Decorators and Marks page. Apparently Iain worked at the Troika factory since 1970, but his name or marks don't show up in any of the reference literature for Troika.
I saw the massive Troika auction, including the double egg cup, at the Clarks Auction Rooms sale page, but wasn't able to bid on any of the items. Unfortunately, Clarks didn't include a photo of the bottom of the egg cup showing the mark.
I am eager to see your double egg cup. If it is indeed by Iain Draper, you might have a rare item!