There is a whole bunch, although they are not really all that great. You can use this one from the unfinished tt-rss android app:
https://github.com/gothfox/Tiny-Tiny-RS ... i/icon.png (svg version should be in the repository too)
You can also use those, but they are small (I've done them a few years ago for the firefox notifier):
http://madoka.volgo-balt.ru/~fox/tt_icons/And I also have a few other SVG prototypes lying around, but I'm not sure where exactly. If you can't pick any of the above, I can look for those I guess.