I don't think I've ever seen flat head intonation screws before, but you obviously do have them. I wouldn't put it past Fender to have had them at some point in the past.
Here's a photo I found online of a bridge with the long intonation screw like yours:
Edit: It seems that at least some old Telecasters (60's era) used flat head intonation screws, so the odds of Fender using them elsewhere at some point is more likely than I first thought. Then again, they may just be regular screws from a hardware store.
Here's a photo I found online of a bridge with the long intonation screw like yours:
Edit: It seems that at least some old Telecasters (60's era) used flat head intonation screws, so the odds of Fender using them elsewhere at some point is more likely than I first thought. Then again, they may just be regular screws from a hardware store.









