7 speed STI Levers
Does anyone make them? Or will 8 speed STIs do the job?
cycles per second
Shimano made them. You may be able to find some over at www.loosescrews.com .
8-speed levers will also probably work for 7-speed (I have some friends who do this) since the cog spacing is very close (5.0mm for 7-speed, 4.8mm for 8-speed).
I think that you might be able to find 7-speed Sora levers. Otherwise you'll be looking for used or NOS stuff.
Whether or not 8 speed STI's will work with a 7-speed cassette depends on how picky you are. I've gotten them to kind'a work, but they don't index perfectly. You'll probably find that you have to double shift in some situations.