I had a list of three items when I went to Staples; copy paper envelopes and an Epson 786XL magenta ink cartridge. The store didn't carry individual colors--just the package of 4 for over $100. I ordered the ink direct from Epson; your loss.
The glue they used to stick the reams together was all over the sides of the paper making it useless to feed into the copier. Paid a few more bucks for the Blue Hammermill Copy Plus and its been great.