That sounds like a lot of crayon to me, but your vet sounds good. Pumpkin puree is a great way to get wet fiber into him, which is what he needs right now. Just keep an eye on him in case he stops pooping, in which case he'll need some more intense home care and/or a vet visit. When I'm worried about stasis happening, I make sure I have liquid simethicone (baby gas meds), pumpkin puree, parsley, romaine, dandelion leaves, or spring mix, pedialyte (unflavored is best so you can flavor it to his liking), probiotic such as Bene-Bac or Probios, and maybe a fresh pineapple. My guys don't really like the pineapple, but it can help in some cases.
Bene-Bac is available in the dog/cat medicine/supplement section of many big box pet stores--I like the big tube instead of the smaller tubes. They also make a powder for small animals but it's harder to find. ProBios is made for farm animals and can be found at feed stores. I just got a bunch at Farm and Fleet yesterday (a WI farm store) and it's cheaper than Bene-Bac. I got a powder that's for all sorts of animals, including "exotics" (rabbits), and also a gel that's made for horses.