ZVOX Z-Base 220 TV Surround Sound System $79.16 Delivered @ GraysOnline eBay
If you are still using your TV's internal speakers, this is a great upgrade for a great price as long as you don't mind the size of it (quite large in depth). It's a bit of old product but nice speakers are nice speakers. I highly doubt you can get better speakers for the price.
Bonus round: Since stock level is low on this (2 left as of writing), I can't post this one below under separate thread - price is $379.05 after PUSH5 (RRP is approx. $849). I bought one myself.
Canton DM9 2.1 virtual soundbar
Product website Link: https://www.canton.de/en/home-cinema/tv-soundsystem/dm-9
If you're not familiar with Canton, it's a very popular, good quality speaker brand from Germany.