Replacement C/D mudguards from India are showing up on eBay and elsewhere.
http://www.ebay.com/itm/261484645471
I had the misfortune to order a set and they do not match the originals and, worse, simply do not fit. The suppliers are not helpful and charge a non-refundable fortune for shipping. Thankfully Tino Sacchi is now producing replacement C/D mudguards and, if they match the quality of his other parts, should be brilliant.