Its 109 on the silicondust website - assuming you are in US - and amazon
https://shop.silicondust.com/shop/product-category/hardware/?scrollto=663471
Assuming you live in Beaverton you should be able to pickup KUNP (Univision Portland) and KJYY (Telemundo Salem, rebroadcast from Portland) Over The Air (OTA) for free.
https://www.channelmaster.com/pages/tv-antenna-map-beaverton-or-97077
Buy a network TV Tuner:
SiliconDust HDHomeRun Flex Duo 2 x ATSC Tuners - HDFX-2US
Buy an antenna if you don't have one:
Once you plug it into your wired network you can use an app called HDHomeRun on all of your in home devices including FireTV to watch OTA TV for free.
If you cannot afford the network tuner you could also use your TV's integrated tuner. You'll just need an antenna then which are inexpensive. Though you'd be tied to that TV instead of being able to watch elsewhere in the home.
If you don't want to run cabling and you have a decent network connection, you could try a network-enabled antenna DVR. This way, you'd connect the antenna to the DVR, and your TVs would use a streaming stick to play the live feed from that. Bonus, you get recording functionality as well.
Some options include the Fire TV Recast and the HDHomeRun (several models available).