For in-store pickup only, with stock varying by ZIP, Sears offers the HP c2500 Wired Keyboard / Mouse Combo, model no. H3C53AA#ABA, for $19.99. At final checkout that drops to $14.99. Plus, Shop Your Way Rewards members bag $10.75 in SYWR points. (Not a member? It's free to join. Credit amount may vary slightly by customer.) Assuming you'll use the credit, that's $13 under the lowest shipped price we could find. The mouse features three buttons and 1,200 dpi, and the keyboard is fine too, purportedly.

Of note, Shop Your Way Rewards members may be eligible for additional credits and discounts.