The NTE3098 consists of a phototransistor optically coupled to a gallium arsenide infrared emitting diode in a single 4–Lead DIP type package.
Full spec sheet:
https://www.nteinc.com/specs/3000to3099/pdf/nte3098.pdf
NTE3098 Optoisolator Phototransistor w/ NPN Transistor Output, 4 Pin DIP
SKU: NTE3098
$2.64Price