http://www.safergrass.org/pdf/AftertheCrash.pdf
There's a venogram on page 12, figure 9.
I've encountered significant variation in density of blood vessels the LCs I've dissected, but compared to other cartilage structures, the LCs are quite profuse with blood vessels.
I have also pumped a significant amount of blood out of a cadaver by creating a small opening in one the LCs and loading the limb from the carpus - like squirting blood 20 feet across the room. Makes for an interesting demonstration, but it only works with a fresh cadaver that has not been drained of blood. Most cadavers I have gotten from a renderer were from horses that laid in the field for a while before being picked up. Or they have dried out in a freezer and the tissues have lost a lot of water, thus the blood and the vessels containing it have shrunk. Once in a while I've gotten them fresh from clients who have lost horses - same day, immediately vacuum bagged and then frozen. This makes a better specimen for dissection.
When you consider the actual blood volume of the whole foot, the LCs can contain several tablespoons full of blood each - more than the various other venous plexus. But the evidence of blood volume in the LCs is also obvious in a venogram.