You should be able to replace it with any standard vac hose. I usually just take it to Oreilly's and buy 5ft of whatever size hose I need so I have some in the future as well. The only exception being the molded vacuum hoses... I try to buy those OEM if I can because if one part was brittle... chances are the rest of it is also.

Actually I just today replaced a ~1ft section of vac hose going from intake manifold to fuel pressure regulator on my 87 325 BMW. So having the extra hose lying around helps... but then again I am maintaining 5 bimmers atm so you may not get as much use out of the extras as I do.

edit: btw, did you have mice living in the back of your engine bay at some point? Looks like a nest on your pic.

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2005 X5 4.4i Build 04/05 Maintenance/Build Log
Nav, Pano, Sport (Purchased 06/14 w/ 109,000 miles) (Sold 8/15 w/121,000 miles)

2006 X5 4.8is Build 11/05 Maintenance/Build Log
Nav, DSP, Pano, Running Boards, OEM Tow Hitch, Cold Weather Pckg (Purchased 08/15 w/ 90,500 miles)

2010 X5 35d Build 02/10
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