Roy advices are spot on!
The Roland JP-8000 is actually also quite
cool when it comes to Arp Odyssey-like sounds,
belive it or not! I got onr myself and I´ve programmed some really cool sounds on it.
And of course the is the Odyssey-clone:
The Prodyssey manufactured by Creamware.
If you go down the software road: The Oddity
from Gmedia is quite cool too - though it`s software. I once programmed the Currie-lead on it and it came really really CLOSE!!!
I can send it to you - if you are interested.
Last - a lot of the synthsounds on Rage In Eden
was done on the Oberheim OB-X - including some of the leads too (read that at the Matrixsynth website) - and when you listen to the Rage In Eden album it actually makes sense (too me).
Sonicprojects have done a COOL soft version of the OB-X: The OP-X and the OP-X Pro with multimode filter - one of the absolutely BEST softsynths money can by today. When you hear it, I bet you`ll say: Ahaaa... http://www.sonicprojects.ch/obx/description.html
They also make a really cool stringer (while we wait on the one from Gmedia
If you are totally into Billy Currie and OScar:
By the impOSCar and the Billy Currie signature soundset from Gmedia!
Good luck and all the best!