1. Don't know on the knobs, they all seem to be hard to come by. I don't think Ibanez makes them anymore. You can find them occasionally on the bay.
2. You can get the pressure pads from Rich pretty cheap, go to 'parts' and then nut parts. They pop up from time to time on the bay as well.
3. No idea.
4. I believe the bridge and neck were both Floyd spaced.
5. The original correct case is the Jem1000C, they switched in '90 to accomodate the longer UV 7 strings.
http://www.ibanezrules.com/used.htm#Cases They are hard to come by, especially in good condition.
I guarantee you they wouldn't be those prices if they were easy to come by. I bought 2 cases from Rich about a month ago, and about a week after I got them there was another one on the bay, not even in as good of condition. It sold for much higher than I paid for either of the ones I got from Rich. You will hunt for a long time to try to 1. find what you are looking for, and 2. to do better than Rich. In the end, you will save yourself a lot of headache and time by just getting it from Rich to begin with.
Don't just take my word for it, anyone who has dealt with Rich will tell you the same thing...