Putting that kind of stuff on there might just make it harder when someone eventually fixes it (more &&&). On top of that, using the worng product can foul the oxygen sensor. Keep in mind that the manifold moves considerably as it heats up and cools down.
There is no temporary fix. The job needs to be done right and it needs to be done sooner than later because it will mess with the 02 sensors performance and cause eng and cat converter damage that will be a lot more than $2k.
$2k seems a bit high though. I would check around with some independant shops for a better deal. Maybe even consider headers.
Good luck!
Scott