82 f150, 302, headers, dual exhaust

I think that I have a leak from my headers... Im getting an engine variable flapping noise, almost like the fan is hitting on something (but its not)... If I can decribe what it is in words, it would be like what noise you get when you stick a peice of paper in a fan.

quiet at idle, loud during acceleration/loads... I think its the header, but I HOPE its not something more serious (ie lifter)

Hard starting, and its not running very good (kills alot)... Its lowerering the vaccume too (vac gauge installed in dash, for fuel economy)

And, the header bolts are rusted on pretty good, from the looks of it.
Ill be soaking them in PB as much as I can (at least everynight, hourly after school), for a few days... Then ill give a turn on them.

Anything else I could do? I've had it with my truck... about ready to push the SOB off a cliff.

Is this even a leak?

Can I get new bolts somewhere? (what lenght/thread size?)

Tks alot
~Nate