I checked GNC and thye only have 500mg tablets and I've read to only take 100mg for migraines. CVS only has this GelStat Migraine oradose thing, that doesn't say how many mg are in each dose on-line.
At Chamberlins you can get a softgel by NewChapter called Supercritical Feverfew headache relief. It has 125 mg of feverfew per softgel. It's worked for me a few times but doesn't work all the time, although nothing really works for my headaches I hope that helps ya!
Chamberlins is a health store (ie. healthy organic foods, herbal remedy products). I'm not sure if there's many of them throughout the country though. You could probably find the product at a drugstore near you.
I found a vitamin "store" on-line that has it, so I'll most likely order it from there since CVS didn't have it and I don't really have a lot of extra time to go searching for it.