Trips to the Amazon aren't something you'll see offered by the typical tour operators in Canada. I'd put it in the category of a specialty trip, where someone is just piecing it all together manually (flight on a major airline, and adding in some accommodations and a tour/cruise through a local tour operator).
Best thing to do might be to get the details of the U of A trip, and Google around to see what it would actually cost for you to piece together the same trip.
Googling 'university of alberta amazon river trip' brings up a PDF file with the details.
Roundtrip flights:
YEG to Lima (LIM) - $1016
LIM to Quito (UIO) - $400
5 day Amazon river cruise from Nauta on the La Amatista ship. I'm guessing it's something like this:
http://www.perucusco.com/cruises-mar...uta-river.html
Which looks to cost $1550 USD/person.
Accommodations:
Casa Andina:
http://www.tripadvisor.com/Hotel_Rev...co_Region.html
Looks to run about $130/night. So $260 for 2 nights, but I'm guessing you're probably sharing a room with someone on this trip, so let's say $130.
El Dorado Plaza:
http://www.expedia.ca/Iquitos-Hotels...el-Information
Looks to run $260/night. So again, divided by two people, let's say another $130.
So far, it looks like it would cost someone $1016 + $400 + $1550 + $130 + $130 or $3226 to build a similar trip on their own. But there's likely some excursions and maybe some additional meal costs that haven't been factored in yet. And also any additional ground transportation.
So overall, $4200 doesn't seem too out of line considering the components involved. The Amazon river cruise does look to be the biggest expense, but for a smaller ship that can get you further into the depths of the Amazon, I'm guessing it's probably always going to have a pretty hefty pricetag of around $250-$300/night. Gap Adventures for example, is charging $2500 for 9 nights in January...
http://www.gadventures.com/trips/ama...ate/2014-01-01