I tried searching in
wmploc.dll using Resource Hacker, but couldn't find it there. I need a higher resolution (as much as possible) version of this icon.
Photos app icon. You can find it at the following location as a .png file (multiple variations):
To have access to the WindowsApps folder follow the instructions I have provided to another question here: https://superuser.com/a/1205874/552853
In case you don't want to make changes and just want this icon here you go:
(the highest resolution is 336x336)