There are a number of contemporary packs around that feature older full length designs.
Some of these - particularly Simon Wintle's Original Woodblock are of interest in their own right, as packs to admire and enjoy.
However, there are also one or two that could be passed off as genuine antiques by an unscrupulous seller.
It would be clear from handling the modern reproductions that the cards are modern.
Older cards were laminated and quite thick and the card face was rarely perfectly smooth.
Different cards in one pack vary a tiny bit in size (so the edges of a deck are a little rough).
Avoiding fakes on ebay
Visually: The old cards should have no indices, square corners and of course plain backs!
Old cards were also rarely perfectly rectangular.
Also the colouring should be clean ivory to cream, a number of the reproductions have overdone the sepia effect!
Simon Wintle recreated the techniques of the 17th-early 19th centuries, printing the outlines of the courts with handmade wood blocks and adding the colours and all the pip cards by hand painting over stencils. A new set of courts weas specially designed, and the jokers, while not a period feature, do seem to fit very well.
Simon Wintle has kindly provided an image of an uncoloured woodblock print for this design , a sheet that can be compared with Hewson Sheet P7
For more information see http://www.wopc.co.uk 
With this pack, Simon Wintle has created a reproduction of the Hewson cards (see P1) based on known examples. The pack was made to supply period film sets and so on, as well as being of interest to collectors.
Again, see http://www.wopc.co.uk/
This is a convincing set and includes a convincing tax wrapper. The wrapper is a little too dark brown, and the card modern, but this would be undetected on a web browser. The set is a pleasure to own - like a real set without the worry about its value!
The Ace of Spades - sixpence additional duty - is too early to be a real Stopforth. The card is also thin, but otherwise a very nice and fairly convincing reproduction.
This is more of a luxury pack, with smooth card surfaces, round corners and a portrait of Queen Victoria on the backs
Bass produced this replica set to commemorate its 200th anniversary (1777-1977) and wanted cards typical of its founding year. These are probably a little later. The cards are modern in feel with a smooth finish and the Bass logo on the reverse. This comes with a booklet of popular card games of Victorian times.
This set was produced by De La Rue themselves to commemorate their centenary around 1932. While this is itself a collectable item, but could easily be passed off as a set almost 100 years older. If anything, the 'aging' appearance has been oversone, and the original cards would look cleaner!
Compare with an original, see F44
This is a late 18th century forgery of a Blanchard pack. The thing to look for first is the Ace of Spades - the genuine tax aces were prepared by the Stamp Office (part of the UK Inland Revenue) and engraved in fine detail. This ace has been printed by wood block. The forged ace always seems to be numbered 59.
Jean Verame has an example in 'Sublimes Cartes à Jouer', plus a modern recreation made for Stanley Kubrick's film Barry Lyndon. This latter pack is an unusual recreation being a copy of a copy and its provenance guarantees continuing interest.
So this is a C18 pack in its own right and with its own story but it is not a real Blanchard.
At last! A full-length design with indices. (If you see why this is funny, you are probably as obsessive about cards as I am, and you are probably named Ken.) This is one for the bridge and poker players. "American Manufacture" was the first designation used by US makers when they started production around 1800 and onwards. This is a very well presented luxury set and I like the backs which appear as 'invitations to the ball'.
This is a good modern copy of L I Cohen's Highlanders from the 1870s, Hochman type NY3.
Compare with an original, see I64
This is a re-issue by the manufacturer of an older design from 1894 (of general type US8).
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This is a very high quality but modern-feeling deck, reproducing Andrew Dougherty's Illuminated cards type AD3.
Compare with an original, see I65
