The B1 is inexpensive, so why not get one and experiment with it?
It's not the only bandstacked C-band unit I've read about, but the only one readily available in North America (that I've noticed).
I'm sure Tron will be on later and can offer encouragement for you.
He uses one in his setup.
I'm pretty sure a C2 from SatelliteAV will outperform your 741 on C-band alone.
It's not expensive either.
You can hook it to a multiswitch for distribution to several receivers.
There are drawings in the Switches Simplified FAQ to help you.
Probably the best results come from a C-band-only ortho mode feedhorn and two decent LNBs.
That could set you back $75 to $200 , plus a multiswitch .
Few months ago, we had a nice thread on orthos with all the why's and how's.
If you want to go that route (it's not hard) and can't find the discussion, I'll look it up for ya.
What size dish are we talking about, and what programs are we looking to get?