I have both thigh braces with the female insert intact. I saved the screws that go there too. They are for an old H2 but maybe they'll might work in the H3 if the H3 doesn't have the ratchet outfitting attached to the thigh brace. These are the old school ones without any ratchet interface. Let me know if these will work for you.
If you live in the Denver metro area I can meet you at the Golden play park. Otherwise I can mail them to you. You can have both of them. Don't worry about shipping... I'm rich, beeyatch!!! (not really, but you still don't have to pay for shipping or the parts). I figure that if I'm nice to kayakers it makes up for being such an asshole to all the regular people who piss me off.
Send me a PM to arrange for the transfer.