Ricks has them for $65.50 shipping included, was the best price I found.
One thing about these Norsat and CalAmp LNBs, is that there is quite a spectrum of quality and price. You can get a low cost LNB for around the price you mentioned, or you can pay twice that or 10 times that or even more. People tend to look just at noise temperatures on these things, but there are other important specs, like frequency stability and phase noise.
Back when I was analog only, I had a fairly cheap CalAmp. When the switch to digital (DCII) started, everyone was saying that our current consumer LNBs weren't going to be good enough. I decided to keep my old one and try to get by, and it seemed to work fine, although it later died, so I bought a slightly better LNB, a Norsat with a .75 MHz freq rating instead of the approx 1 Mhz rating of the cheaper LNB, however I didn't notice much difference.
A few years later, however, when DVB-S2 came out, everyone was saying that you needed bigger dishes and higher quality LNBs, so I bought a slightly better Norsat LNB, one that has freq drift ratings down around 0.1 MHz. Again, I found that I didn't notice much difference, and in fact if anything I had a harder time locking the S2 channels, mainly because the stability was apparently a tradeoff for gain. So I actually switched back to my old .75 Norsat, although I've been thinking of giving it another try.
A lot of people recommend getting even higher quality and higher cost PLL LNBs, but I don't think I'm going to invest in one of those unless I see one cheap on ebay.
But anyway, the gist of what I'm trying to say, is that there are many many different models of Norsat (and other brands) LNBs, and one of the advantages of having a feedhorn is that it is easy to switch LNBs if you want to try for higher quality. It's tempting to go for the more expensive ones, however I think even the cheapest Norsat is probably higher quality than any of the LNBFs available, and since there seems to be a tradeoff of gain to get the higher stability, I really think that most people would be just as happy with the cheaper LNBs. I think if you are getting your gain and adjacent sat rejection from the dish, then the high quality LNBs will give you a better signal, but if your dish is marginal size, then I think you're better off getting a bit more gain from the LNB, which is usually going to mean the cheaper one is the better choice.
Ie, I think the $65 Norsat is a good choice. I got my most recent ones from one of the sponsors at the Satforums forum, who is pretty reliable and helpful too, in case you want another source.