You might be able to find someone selling seat covers or old OEM civic seats for cheap. I know I sent a mint set that came in my hatch for about $30 for the pair, and actually had a hard time getting rid of them. But if you can find them, I would recommend getting some del sol seats since they are a lot more comfortable, and actually feel good on my back unlike the terribly uncomfortable and unsupportive civic seats. They can be pricey though. They generally go from $75-$300 for a pair.
For the visual learners out there...
From these civic seats:
To these comfy del sol seats:
The most worthwhile "mod" I've ever done to a Honda!