Couple of 3+ lb bags of very old Kodak Sodium Thiosulfate
Some time ago, another member here offered the remains of an antique 100 lb drum of Kodak Sodium Thiosulfate, free for the taking. Since I was local, I took it. I've given a lot of it away, and thought I would offer a wider audience the balance. You should be aware that the stuff is at least thirty years old (newspapers dated from 1979 at the bottom the drum).
I have two bags of the stuff to give away, both bags weighing about 3 1/4 lb. When I picked the drum up, the contents were one solid crystaline rock. It's not hard break up, however. The two bags are full of chunks about the size of an infant's fist. I put nitrile gloves on, and rub a couple of chunks together until they're ground into small easily soluble pieces.
You can pick these up in Southern Westchester, New York. I'd be happy to mail them to you, if you pay the postage. I beleive one bag would fit into a USPS Medium Flat Rate box, and one of those costs $11.35.