It sadly seems like they're beyond repair
Eric Voskuil, known for his book and blog both titled Before Mario, made quite the discovery recently. For the first time in his 20+ years of collecting, he found a couple packs of souvenir playing cards featuring Kyoto imagery produced by Nintendo back in the 1950s. However, upon opening them, he tragically found that they had all fused together into one block of paper.
While this is still a cool discovery regardless, it’s a shame that the individual cards can’t be documented. Here’s hoping that, by some miracle, somebody out there still has these cards in good condition.