capacity has nothing to do with compatibility. We have a list of compatible media on the manual and some are large (IBM). SanDisk has a basic line of CFCards available on line. I'm sure these cards can also be ordered thru retailers.
we usually advice to stay on lower capacities as Eclipse won't really use a lot. A 16MB is more than adequate. Of course, like for any other technology, progress is fast so today capacities are big. That's fine! You can use them…but try to stay on lower speed cards series as many of the ultra fast/extreme cards (good for pro_cameras) may not be compatible.
If you check this link to SanDisk:
the SanDisk STANDARD CFCards line is the one you want to look for. It's the one w/the blue label. It comes in different sizes:
256MB/512MB/1GB/2GB/4GB stay on the lowest possible you can find anyway.