Probably offer up around $20-30 dollars. That should bring the designers out to play.
Specify that you want it in vector if you have no source file right now, it will be easy to edit as well for any designer that has even a pinky full of talent.
Vector is scalable and keeps it's resolution as you resize it.
Else, if you are feeling adventurous..
You could download a vector program and give a go yourself..
Depends on how creative you are. If you suck at design, I suggest a contest.
For the designing point of view i think this font is not easy to read, if you remove this font and use university font or a tolkien font. Its color scheme is good if you want to change this color scheme i suggest you black and red color combination.