I'd buy a few used (but BMW Genuine) FSRs on ebay.
I bought qty =2, about $15/each.
Keep an extra FSR on glovebox as spare.

No need to buy new (which is $100 or so).

Stay away from aftermarket for now.

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1998 E39 528i 5sp MT
2006 E53 X5 3.0 6sp MT