I just joined and this is my first post lol. But I wanted to say that I have the box and crayons from when I was little :) so glad my parents kept them.....my boys use them now. We do have new ones as well so they each have some and then some at my parents :)
Waldorf teacher Steve Sagarin discusses block crayons and many other aspects of crayon coloring here:
I had the Stockmar crayons as a child, so I know their texture. That said, if you already have stick crayons at home, preferably a bin of broken ones, they're super easy to melt down. We had some tin heart shaped baking molds we got at the dollar store that were a touch too small for cookies - I was going to make soap with them, but anyway. I melted some plain old (and I do mean old) Crayola's down into the little heart shapes, and they came out great. They're not breaking at all and the kids can either shade with the sides, or make sharper lines with the hearts' tips. It recycled a bunch of nonusable crayons, and are a lot fewer pieces to keep track of than previously. Just a thought in case anyone feels like being thrifty.