Where are the brightness/volume icons for BezelUI stored in Sierra / High Sierra?

As the title states. I'm using [OSDisplay](https://github.com/zulu-entertainment/OSDisplay) (as a sort of answer to my question [here](https://apple.stackexchange.com/questions/245882/is-there-a-way-to-display-an-instance-of-bezelui-brightness-hud-volume-hud-us/321096#321096)) . I've noticed that in Sierra (or so it seems), the OS's icon for the brightness HUD changed some—longer and thinner rays, thinner inner circle, etc. I would like to change the file that OSDisplay uses so that it matches the default icon. Apparently in the past these images were stored as PDF files in /System/Library/LoginPlugins/BezelServices.loginPlugin/Contents/Resources/BelzelUI/HiDPI, but I do not see them there any more. The Contents/Resources/ folder just contains a bunch of .lproj folders.