I'm looking at buying a scrap yard head (as soon as an SPI comes in from a collision) and giving it to an engine head rebuild shop. That's pretty much all they do is rebuild heads, mostly for tuners, but I'm sure they could handle my SPI. I'll have to talk to them to be sure they can get upgraded seats though, they do mostly upgrades for the tuners so hopefully their source for parts will have something.
And a note to the OP. 128k KMs, WOW that's some low mileage, mine has 222000 and its also an 02.
As far as the vibration, my mount under the airbox was brutal as well, but replacing it did not solve the issue, pop the cap off the passenger side top mount, mine was bulging up, and replacing that one smoothed things right out. I think as the engine warms it up, it helps, but I'd look at that one.
Somewhere there's a DC10 struggling to get off the ground. I'm not a fan of wings on street cars, I like low key spoilers, but not something that you have to custom order from Boeing.