The unit cost of the F-35B plane is said to cost about $123M and they have spent close to $1.508 Trillion and they have so far manufactured about 231 units and the contract will run up to 2070. Even though its costly, i think its too late to abandon the project due to the amount of money spent on it and i really doubt NATO will purchase fighter jets from the Russians which individual unit cost about $50 M. Way cheaper than the F-35.
Hmm... I don't think that the NATO will scrap the F-35 project. But at least they should audit the expenses, to make sure that tax payer money is not wasted in the future on such useless projects.