The SB6183 cable modem has been selling for around $67 for the last six months. Right now it's down to $54.13 when you clip the $7 off on-page coupon.
Cable modems need a wireless router to distribute the signal, so grab the Nighthawk R6700. It's a really good router with a $10 off on-page coupon.
Be sure to check with your ISP to make sure they support the SB6183 cable modem. It still has widespread support, but it's an older model and no longer compatible with some services.