with that budget your options are extremely limited. you might as well look for a used Church preamp (ugly, 9100 or 9200) or a Sound Professionals SP preamp if you're running Church mics and Sound Professionals mics.
I would stick with one of the Church models. Noise specs are better than SP's I think.
9200 is great, but I doubt if one can be had for close to $100.
I would go with an UGLY if you prefer battery box size and won't need to change the gain at the show. According to Chris Church, set the gain knobs at about 90% (1:00) for a loud show and all the way open for a quieter one and use the recorder to adjust your levels.
If you want to be able to tinker with the pre's levels at the show and don't mind the larger size, get a 9100. I prefer the 9100 since I don't find it a problem to stealth with.