09/09 Update: Unfortunately, this turned out to be a complete fake! The buyer contacted me when he received it, concerned that it didn't seem right. I asked him to ship it to me for my personal examination. I received it today and his concerns were justified. Here is what I wrote to the buyer:
I received the package this morning containing the fence and its envelope. I just now carefully examined the contents. They are, without a doubt, fake.
The envelope is the clumsiest part of the fake. The forger took pains to make it look old with ersatz staining and portions missing from under the flap. The wear and the missing portions are inconsistent with true age and true usage. The forger is not good – and we should be grateful for that. You can actually see a blue line along the left obverse side like they decided to repurpose some other paper. The weight of the paper is inconsistent with every truly genuine Whitney envelope I possess and have examined. The greater size of the numerals, 77, is inconsistent with every truly genuine Whitney envelope I possess and have examined.
The four fence sections are also poor copies. They are on paper weight that is much too thin. The colors are washed out. There is a lack of the detailing that my authentic set possesses. The trimming done on the fakes is poor and inconsistent with authentic examples.
The fakery is consistent with the garbage I’ve seen two eBay sellers pawn off as genuine on unsuspecting buyers for years now: shadowtown and curiousimp.
I am distressed that another nice vintage set has been faked! You cannot be too careful these days!
Importantly, I have spoken with the seller who, I completely believe, was duped himself when this item was purchased some years ago. He immediately refunded the buyer's purchase price. He and his wife are long-time generalist antiques collectors who, like the rest of us, can't be expected to know a lot about every collecting genre. I only wish other sellers, when learning they had been duped, were as upstanding and as responsive as this fine seller.