The prototype E-7 cost $2 billion. It's a 737 with some radios.
reply"On 22 March 2019, the UK Defence Secretary announced a $1.98 billion contract to purchase five Boeing E-7 Wedgetails"
replyPrototype price isn't really that meaningful
(Also it's a 767 not a 737, that was the E-3 I think.)
You must be thinking of a different boondoggle, the E-767, which is the obsolete radar package from the E-3 bolted to a 767. The E-7 is a 737.
replyAh right, it's a bit confusing between the bunch of these.
replyNonetheless the price tag was only $400M/ea E-7 for the UK in 2019 (usual later price shenanigans not included)