Despite being simply titled Silent Hill 2, the American PC version also contains all the extra material. Two different variants were released with differently sized boxes with different catalog numbers and barcodes. This is the small box variant.
It came with a manual and three discs in plain black paper sleeves.
3. Inside of box
5. Disc 1
6. Disc 2
7. Disc 3
Thanks to Felix M. C. Li (image 1) and alf717 (images 2-7).