https://www.youtube.com/watch?v=_CwNK5kqYBMEibach, you can't beat German engineering when it comes to springs. Around $200 for the 88-91 CRX. The ride comfort is okay, won't be as good as your stock springs so I don't know if it's worth it for fuel economy. But since it's long distance and highway work only, you should be okay. Anytime you lower the car the comfort will never be as good as stock settings unless you get the other setup:
For about $1200, you can buy Koni yellow shocks + Ground Control coilovers (they use Eibach springs) will be the best balance of comfort/performance, and is in the fact the only way of dropping your car without sacrificing ride comfort.