Since the ruling against Ninestar, the only Epson cartridges that can be sold by small shops like O-ink, besides Epson Brand, are refilled Epson cartridges that the cores come from the USA.
Now this is fine for most Epson cartridges. Some of the old models and some of the pro series of printers, those cartridges are hard to come by, but any of the seven pin cartridges are an easy find. Let me explain Pins, when I mention pins, I mean contacts on the chip that Epson puts on the vast majority of their cartridges.
However, around a year, year and half ago, Epson came out with a new chip, a nine pin chip. This chip has a micro-fuse built into it. So what is the problem you may ask? When these printers that take the 9-pin cartridge read the cartridge as empty, that fuse burns out. Rendering the cartridge completely useless. While people in my industry are looking for solutions, currently you are stuck buying new Epson Brand cartridges.
What about the at home user looking to refill cheaply? With both the T069, T077, and T078 series of cartridges they can not be done. Until someone legally designs a replacement chip, or figures a way to prevent the fuse from going, we are out of luck.