@theme-ui/presets (0.2.44) MIT
Theme UI includes an optional presets package that can be used as examples or as a starting point for extending your own themes.
Although https://openclipart.org/ has been down for over 6 months, you can still find the original collection of 8000 cliparts dating back to 2005 at various sources. The project is currently using SVGs found in the openclipart 0.18 package. I'm pointing to Debian Jessie, but later versions are identical.
All SVGs are in the public domain.