If we're just talking C-band only... (a wise decision)...
Then only two general solutions come to mind.
1).
The C2 from SatelliteAV already mentioned, is quite well regarded.
This
thread says the 242 from Galaxy is equal.
2).
Orthomode !
It's a little more expensive, but reasonable for C-band only setups.
Learn all about 'em in this
previous discussion.
Be aware, that a larger dish also decreases the interference from adjacent birds.
This also makes it look like you're getting a stronger signal.