So $800 is (at the exact moment) £597.82.
Shipping from the USA would be in the region of $100, so that's another £74.73. But might be as much as $200 (£149.49)
Using the lower sum that's £672.55 that is subject to vat at 20% being £134.51 = £807.06.
Then there's 3.5% duty on the guitar bit as well - another £20.92
Running total is £827.98 + about £13 for the courier admin fee. So £840.98 delivered to a UK buyer assuming the lower end shipping fee.
So there could be a saving of about £77.45 compared to Andertons if it sneaks though without getting pinged by customs, and about £100 more than Andertons if it gets caught. I've had small stuff get through, but never anything as big as an instrument.
I'm not sure whether Fender UK would deal with any warranty problems for a personal import or not. I'm guessing not.