The last time I bought new carts for my ink jet, (about a year ago) I went to one of the local 'refill' stores... You turn in your old carts for new ones at about half the cost of buying the 'name brands'.
Again, I seldom print much, but the knock-offs have worked well for me --- albeit, when I first installed them the software in my HP printer gave me warnings up the kazoo about not using their overpriced ink. ;~))