Well, I've been aware that Bromoil ink is just a specific litho ink, but it seems to come in pretty large batches (I assume for those who own a printing press?) I did try googling some of the terminology from older Bromoil articles and found this:
Senefelder's Crayon Black Litho Ink Graphic Chemical 1803c
...which I believe is the same stuff B&S sells. So perhaps the ink I got from them was the right ink but was very old or improperly stored? I had to sort of "tear off" a pea-sized chunk, kind of cutting it out of the can with a stiff palette knife, and it took a fair amount of linseed oil to get it workable. Now it's just a solid block of ink, like hard rubber.
Anyway, the link i found is in stock but $35.00 (no size stated), where B&S is about $10... so I assume it's like a quart or something??
Thanks though, hopefully I can find a more realistic size, or I'll bite the bullet. Or start doing 48" bromoils...