Period correct for the Frankenstrat when it had the Prototype FRT 4 installed as well as the Rasta when it had this Frankenstrat neck attached.
This is a New Old Stock Original Floyd Rose 4508 Locking Nut in Gold. String retainer and mounting screws included.
R2 size 1 5/8” / 1.625” 10” Radius
* Note that the mounting hole spacing is a little offset compared to Schaller nuts and your neck may need some modifications before installing.