Amazon and various retailers have discounts on Roku streaming devices: (affiliate links below)
Roku Express (New) HD Streaming Device for $19
Roku Express 4K+ | Streaming Player HD/4K/HDR for $27
Also available on Walmart for $27
Also available on Best Buy for $27.99
Roku Streaming Stick 4K | Streaming Device 4K/HDR/Dolby Vision for $34
Nice savings here.