I don't know what question you have but you can usually type product information into the www.costco.com website search bar and it will bring up relevant products that they carry. Sometimes their help desk will also be able to answer questions about if they carry a product without having to purchase a membership. To get in and buy it though you need to buy a membership, which is usually like $60 or $70 bucks.
THey've crried my Epson ink for many years--for the Epson WF-3640, but I don't know how deep their Epson inventory is. I would call and ask cust service for your specific printer.
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