both of these places are much cheaper than Staples, who I agree, rear end you on their prices.
I used the top link a few months ago and got a black and all 5 colors for the same price staples was charging for just 2 cartridges, so a savings of 300%. :00hour It's a generic brand "G&G", but they have worked just fine. Also, if you buy in bulk, say you wanted to get 3 sets of cartridges, it's even cheaper.
I have bought other items from there, I love my laser printer, First time in 3 years I have had to replace the toner, meanwhile people have to replace whole inkjet printers and cartridges all the time