lol, just read this second message about VRS and keyboards.
Robin, you may benefit from an e-mail group called Sorehand. I think the URL is www.sorehand.org. Many people there are long time sufferers of repetitive strain injuries and they post nearly every day. This group isn't all that active. Sorehand is where I learned about VRS. Many people on the list can give you recommendations on what to consider when looking for an "ergonomic" keyboard and/or mouse. They have tried many innovative gadgets on their computers, include mice they control with their feet and toes ... go figure.
I hope you're feeling better soon.