Are you planning to get your SP-CMC-8's phantom modded for this? If not any small minidisc preamp will do an OK job. I would say get them phantom modded.
The MV-100 is a good pre, but I think you are limited with only -20 and +20 options. However this pre is closely related to the Sonosax SX-M2, which if you are lucky can be found for a steal, however if not usually $750. The sonosax is an amazing pre, i've run mine accidentily at constant overload and still got a listenable recording. It is the same size as the MV-100. There is also an MV-100 on ebay. They are both run on internal 9v batteries
The MP-2 (also related are the Sound devices Mixpre and Shure FP-24) is a great pre, very warm sounding. Don't worry about the rechargable battery mod, all you need to do is peel off a bit of plastic around the + tip of the rechargable battery and it will work. There is a thread here with pictures. I ran this pre when I lived in Barcelona and was able to sneak it in at the Apolo, Palau San Jordi, Razzmatazz, and the pavilion in Badalona. So if I can sneak it in there you should be fine! It is made of metal though so if they now have metal detectors you might be in trouble. It sounds very good with AT mics and personally this is what i'd get. The batteries do not last long if you use rechargables though so be careful.