Duran Duran were heavy users of the Roland Jupiter 8. A lot of the signature sound reflects the JP8.
I'm not certain, but I'd be pretty sure that the JP 8 was used for that arpeggiator sound.
Unfortunately I'm not aware of any refills that feature the JP8. There's plenty with Jupiter 4 sounds - but that is a very different beast.
Assuming you won't be in the market to find a second hand Jupiter 6 (has MIDI) to use with Reason 7 when you get it
, I would suggest you consider evaluating arming yourself with;
- Bitley Platinum - no JP8 that I'm aware of, but it does have JP4, and nice JX pads and strings that are not a bad substitute. This refill also has plenty of Fairlight sounds - another instrument Duran Duran used a lot.
- Kings of Kong - this refill has Simmons Drums on it - also used by DD.
- Synapse Antidote synth. It's no Jupiter 8, but you'll get some very nice retro fat sounds using this that will be great.
best of luck. Would be great to hear your covers on Soundcloud!