From a photo of a real pre-NTI Apple-1.
F 74S257 DC, gray ceramic.
7613 date code (also seen with 7617 date code).
Total # on board: 4 (locations B5 - B8).
From a photo of a real NTI Apple-1.
Vertical labeling, black plastic, stretched “S” logo, no added S below part number.
Total # on board: 4.
F 74S257 DC, gray ceramic. 7613 date code. Exact date code and labeling match to the real Apple-1. On my Mimeo currently.