Sorry, for my late answer. I didn't thought about sharing the graphics part of Obarun, good idea.
Why you made a extra work? i'm the creator of the obarun logo , so i have all the source ;).If you want it , just ask.
Anyway, you can find the logo (and some declination) with svg format here :
http://www.repo.obarun.org/ob-graphics/
Jean-michel, mail me your .png and i will add it on the server