Global Toner via Amazon offers the Ink e-Sale Brother-Compatible TN660 / TN630 Black Toner Cartridge 2-Pack for $19.99. Coupon code "DMSXOQJ8" drops the price to $14.99. Plus, Prime members receive free shipping. (Non-members can spend $49 to qualify for free shipping; otherwise, shipping costs $7.83.) That's the lowest total price we could find by $10. It's compatible with a range of Brother laser printers, including models HL-L2300d, HL-L2340dw, MFC-L2700dw, and DCP-L2540dw.