The little metal bits on the margins belong to metal stands, so you can keep them like paintings
I saw the plates in a thrift store in Romania. Either are the original or they are made again by Royal Worcester.
It seems that, accordingly to the info i found on different sale sites, L’Atelier Art Editions, a book publishing house, made the drawings for the plates.
About the originals :
A Special Donation to the Centre for Arthurian Studies: The King Arthur Plates - A Blog Post