A while ago, two Fiat 133s were for sale on Marktplaats. The owner thought he had struck gold and asked too much for the cars. He wouldn't sell any parts separately either. He managed to sell the cars and the new owner wanted to get rid of the two pumps, for a decent price. They weren't beautiful, but after two months of searching, they were the prettiest I could find. And there was also a rear exhaust bracket (which I did not have because of my switch from 100G to 100GL). So I hit "buy".
One is now (as a mock-up pump) on my Fiat 850 block, the other I am overhauling. I took out Joop's manual, but unfortunately it did not contain much info about the necessary force during disassembly. It turned out that the collar of the lid was completely rotted in the house. Fortunately I still had a few 3-hole pumps and I disassembled one of them today. That was easy and gave me an idea of what I could and could not do. With a nylon hammer I hit the housing quite hard and eventually the lid (where a lot of pieces had already broken off) came off. Fortunately, I still have a new lid and sealing ring in my stash, so I don't have to look for something else and can keep my spare three-hole pumps complete.