TR TF-X KAAN Fighter Jet

[Yasar_TR]

If I recall correct. There was a limited number of engines we could acquire under the "prototype"/ testbed clause or something without senate etc. approval, wasn't that number 20 or something ?

I think you will find that is dictated by monetary value rather than quantity.
Below site defines it in different categories from 14 million dollars to 300 million dollars, depending on the type of equipment and services being exported.
Whilst congressional approval is needed for ammunitions worth more than 1 million dollars, it is 14 million dollars for defence equipment, before congress is involved.

https://sgp.fas.org/crs/weapons/RL31675.pdf