BMW's mod is a metal ring crimped onto the flange, done during manufacture. It isn't a separate part. As usual BMW's solution is to simply replace the entire $500 pump assembly.
Also FWIW I've read of a few cases of JB Weld being permeable to high-pressure fuel when fixing this type of leak, and I experienced something like that myself when fixing a radiator leak with JB Weld... the joint looked completely solid but it still seeped coolant. For the fuel pump fix I might prefer a thread sealant product that is designed to resist high-pressure fluids, available from Permatex and others.
Last edited by smiller; Jul 7th, 2012 at 11:03 pm.