Hello StarlightExp and Roppo.
As I said earlier, this is not a deck that some well-intentioned do-it-yourselfer ought to destroy with a bottle of Elmer's glue.
Lots of history ends up destroyed that way.
One will need the experience and expertise of a professional paper conservator to make an informed decision as to how best to handle it.
The first step would almost certainly be to photographically document the current condition.
This is standard museum practice before any work is attempted.
This should cover Mr Roppo's concern.
The next will be to determine a course of action that will halt any further deterioration, and make the decision as to the appropriate degree of restoration, if any.
I expect they will do some reaction tests, and suggest options for removing the old glue from all cards, as it will only cause continued trouble in the future.
Obviously, the chosen method will depend upon what the glue actually turns out to be, and how both the ink in the images, and the three different layers of paper will be affected by the operation.
For example, the glue may adhere differently on different layers. The wrong solvent may destroy the ink or paper. Manual scraping with a scalpel may, or may not be a safe option. (Though it would certainly be more expensive.) The job may require several steps.
I also expect that a discussion about options for re-assembly will involve some decisions.
Pros and cons of various adhesives, how best to avoid warping or curling, and whether or not to risk the pressure of running it through a press, for example.
The cost/risk ratio may be an issue.
It will likely end up as a lovely thing, but the cost of fixing 78 cards will be significant.
I'll make a wild guess of $25 to $50 per card, maybe more or less, keeping in mind that a bargain hunt could end up in complete disaster.
But of course the buyer is free to do as they wish.
Shuffling it into the ground is also an option.
Anyway, good luck!