while i can't povide you with an adress or something, i can give you the advice to just ask manufacturers if they can provide a try-out-unit. i did this while doing my diploma thesis and was surprised that most manufacturers are actually glad to help in this way, and that at reasonable prices. i borrowed a 24bit-4channel-temperature-logger specifically for pt100 temperature sensors, for around 4 month, and it was no problem.
If you have found a logger which will satisfy your needs, it just costs an email to ask.
hth,
chris