$12 $18
Amazon with teenemo has the Rii Wireless Keyboard & Mouse for $16.49 - 30% off with coupon code VXOIFEMF at checkout = $11.54 with free shipping on $25+ or with Prime.
Best Buy has the refurbished CORSAIR Gaming K55 Wired Gaming Membrane Keyboard with RGB Backlighting (Black, CH-9206015-NA/RF) for $20 with free shipping or store/curbside pickup.
Amazon with VicTsingDirect has the VicTsing Quiet 2.4GHz USB Wireless Rechargeable Full Size Computer Keyboard with Numeric Keypad for $25.99 - 60% off with code LZAG2GFB at checkout = $10.40 with free shipping on $25+ or with Prime.
Amazon with Duolihui US has the Jelly Comb Multi-Device Dual Mode (BT4.2+BT4.2+2.4G) Rechargeable 2.4G Wireless Bluetooth Keyboard for $30 - 50% off coupon (check "Apply coupon" box) = $15 with free shipping on $25+ or with Prime.