if you dig around in the archives at
http://www.emu.com you'll find the latest OS... plus if you poke around the store, you'll find that they have old EPS and ASR-10 sample disks/Cd Roms on clearance...
as for you question about the ASR-X and the ASR-10, the ASR-10 can't read ASR-X files. I don't even know for sure if the ASR-x can read ASR-10 files.