American Science & Surplus is currently selling Jumbo Size Card Decks (5 3/4 inches X 3 3/4 inches)in decks of 54 at a price of 2 decks for $3.95 + S&H. No idea about quality. https://www.sciplus.com/jumbo-size-cards-50423-p Folks in Chicago or Milwaukee can probably find them in stores there. BTW, their catalog descriptions are funny, and they are a fun site to look around if you're wanting to invent an effect: all kinds of boxes, bags, jars, etc., neodymium and other magnets, tools and more.

Thanks! I was looking around for jumbo cards and 2 decks for $3.95 is a good deal. Might have to buy and see how's the quality.

I've seen jumbo Hoyle decks at Dollar Tree - twice the size of a poker deck.

Jumbo decks have caught on in a lot of retail stores in Florida. I've been seeing them pop up both CVS, which sells the Bicycle brand jumbos, and at Tractor Supply, Marshalls and Home Goods in the "impulse-buy" racks.

Recently I've been using an oversized deck of tarot cards. I originally got them for my online readings because they were more visible, but there are a lot of applications in magic.

I have been looking for these cards for a long time, but I couldn’t afford them, but at such a price I would gladly buy

I've seen these at the Dollar General (which is now the 1.25 General. The quality was just okay.

I believe you are referring to dollar tree, I bought several of those jumbos
to make a set of "hold it buster!" by dan harlan.

They are fine for that purpose, cheap and the right size, but there is a lot of blemishes in printing
and they're a little flimsy,

So "the quality is just okey" is an accurate statement, fine for what I use it for though.

I have self laminated these cards - Improves the handling and stiffness.

Be sure to soap the cards so that they handle well.