At least 6 grand if you do it yourself
If youve never swapped an engine before this might not be the best one to start off with. Also your going to need to do some custom fabrication to get everything right.
www.hybrid-racing.com
they have plenty of k-series swap information and since they havent come out with mounts or wiring harness for the crx if you do it yourself you might be able to strike a deal with them as a tester.
If you have the money i say go for it. Youll have one fast as hell crx.