Found this Bosch pump on ebay. Pretty good price, $180, for anyone running a stock pump.
For BMW E60 E61 535i xDrive 535xi 2008-2010 Fuel Pump Assembly 16 11 7 373 521 | eBay
Gaskets Included (Fuel Pump): No. In-Line Pump: N. Pump Only Or Module: Module. Verify that the item fits your car. Outlet Quantity: 1. All orders are processed automatically. New Or Remanufactured: New.
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