I blogged about these reproductions several times in the early days of this website, and added a page on reproductions. Ian Holmes valiantly e-mails eBay sellers to tell them that the items are fakes and were made in the latter half of the 20th century. Some sellers defer to Ian's greater knowledge and change their listings, others argue that they purchased the plaques from 'a reputable auction house', and although other sellers' Flying Cloud Bostons and Agamemnons may be fake, their example is definitely 19th century.
Interestingly, the entirely original plaque below sold on eBay for £27. OK, it is far from being the best example of its kind (!), but at least it has some age to it. Note, there is no title under the transfer. The ship shown is actually the Marco Polo (see the common ships page for more details).