[spacemanspif]

Just Google'd the 2009 Vibe. Looks like the roof rack isn't the type where you can take off the "horizontals" leave the pieces that run parallel with the side of the car. But it looks like you could pull off the racks and reuse the seals if you cut a flat piece of aluminum the same shape as the bottom of the rack mount. Of course this might not be the most attractive option but would cost much less than $150 if you have the tools to do the job. Then there is also RTV and body plugs that could be used in the bolt holes as well...

All depends if you want it to look good while keeping water out, plenty of other cheap options that would keep water out but won't be very pretty...