It's a mite steep but not unreasonably unreasonable, provided the shop (not a dealer?) is using all Genuine BMW parts and has included in the estimate all hoses that attach to the pump and thermostat.
IIRC, all-genuine parts should go for $800-$1,000 from a shop/dealer with no discounts. Figure 2-3 hours labor, plus tax, so at $125-$150/hr you're in the ballpark. The nine-year warranty is atypical so that probably has a non-trivial dollar amount attached, as well.
If it's an independent shop, not a dealership, you could ask them to use OEM parts, instead of Genuine/OE. Be sure to ask whether that equates to opting out of the nine-year warranty, though.
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