are you looking for a KU lnb that fits onto a feedhorn like a corotor ? ebay has lots of listings for those
norsat tends to be popular. others are there inclubibg a basic ku lnb i think its ASC 511 ( i don't have this one or have i ever tried it) should be in the $15 range. I probably have a couple at home (not ASC511's) but it will be wednesday before i can check.
be cautious when searching for ku lnb's at ebay (some sold there do not have the correct LO for noth america so would be usless here )
the correct LO for north america is 10.75 ghz ( could also be listed at input freq as 11.75 - 12.20 Ghz)
or if you don't know just ask questions here or in the FTA section