Since May 2016 agaplatesuk from Redditch in England has been trying to sell these plates. They are supposed to be from Guernsey and the UK (England and Scotland).
They are very suspicious plates. On the Ebay pictures you can see that the blanks have been rubbed hard to clean them before the letters/numbers were applied, Both countries have this very, very unusual style of plate and are for sale at the same time, they are not professionally made, the holes are new, these registrations would be either the original 1904 registrations (they are the wrong type for this) or a much more modern cherished registration worth probably hundreds of thousands of pounds. In that case, they would have come off some very fancy car and be in the current, reflective, white or yellow style or a recent silver on black style.
All the digits appear to be of the stick-on type (that is incredibly rare anyway) and are poorly applied.
Complete fakes almost certainly.