IF you're willing to do the work, an option would be get an HP T730 from eBay, add a low profile Intel quad port I340 or I350 adapter and perhaps add a little m

IF you're willing to do the work, an option would be get an HP T730 from eBay, add a low profile Intel quad port I340 or I350 adapter and perhaps add a little more RAM (depending on the T730 you get 4GB-8GB is more than sufficient), and then install pfsense, opnsense, DD-WRT, openwrt or anything else on it. You will have a great little router/firewall that is much more capable than almost anything else in this price range. NOTE: this is effectively a thin client PC, so you can try different router/firewalls to pick which works best for you. There are also commercial options that people prefer such as Untangle, Sophos and so on. Sophos even has a free home version. There are other alternates to HP T730, but you may have to look around. It should come to around ~$100-$120 depending on luck, since it's eBay.