It looks like there's alot of options available these days on eBay with the running board retrofit kit that looks exactly like the genuine BMW kit.

There's several sellers on eBay that have these kit for around $600, including shipping.

BMW E53 X5 00-06 3.0i 4.4i 4.6is 4.8is Sport OEM Factory Style Running Board | eBay

Or you can spend alittle more and not have to worry about fitment issues, $750, and get the genuine BMW kit on eBay from one of the east coast BMW dealerships that also sell on ebay.

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