Hiroshi Nagai's official site: http://gallery.eizin.co.jp/
Note that not all stuff here are upscales, a few may just be gamma edits, but also serves as a haven to store all the highest quality sources if I find a high enough res scan.
Original Gamma/Color/Edit Versions: lensdump.com/a/LwcSA/?sort=title_asc&page=1
For 16:9 wallpaper crops/edits, I've got them here: lensdump.com/a/LwUCq/?sort=title_asc&page=1
Original Sources: lensdump.com/a/Y3TZx/?sort=title_asc&page=1
Find context on the usage of the original source scans used to upscale this way by searching the respective artwork title: https://www.reddit.com/r/wallpapers/search?q=author%3Aacoolrocket+Eizin+Suzuki&include_over_18=on&sort=new&t=all
