Amazon has Pennington One Step Complete Dense Shade Bare Spot Grass Seed, 5 Pounds for $9.47. Shipping is free for Prime members.
https://www.amazon.com/gp/product…0DER&
Also available, Pennington One Step Complete Dense Shade Bare Spot Grass Seed, 10 Pounds, White, $15.94.
https://www.amazon.com/gp/product…X0DER