That number was also chosen for a very stupid reason. It was the number of F-15s deployed during the Gulf War and therefore apparently all that would be "needed." Nevermind operational loses or Homeland defense or any other commitments. That's what was deployed to fight in Gulf War One, so that's all the Air Force needs for the next war. Yes, I rolled my eyes tooThe real reason 187 were made and not hundred more is because production was spread across 48 states not in the interests of the project but simply for Political reasons.
Had their been a true and proper bidding process the cost per aircraft would almost certainly have come down and dare I say it the quality of some of the kit used in building it would have gone up as well as fewer delays resulting in production overruns further driving up the costs.
The other issue of course is that F15 still ruled the roost as Chinese and Russian super fighter had (and arguably still have not) yet to emerge in any real numbers - so there was no need for it!
Also Britain had a few issues of their own that had upset the cousins - that is sharing super secret stuff with the Spanish (IIRC) - after promising not to
I think this might have been related to the Euro-fighter project - so this last bit might not be relevant if the British instead of develop the EFA/Eurofighter jump in with the USA during the late 80s.
We might see the Germans go joint project with the French but not sure what happens after the wall comes down