So, that is your budget? £60/pr?
You are kind of limited at that budget.
I would suggest, if you are looking at used speakers, you look at the more common Monitor Audio BRONZE, or perhaps the SILVER. These have been made for decade, and you should find a lot of them. The Bronze some in a 5" and a 6.5" version, and the Silver come in a 6" and an 8" version.
Also try finding the Wharfedale Diamond 220 (5") or the 225 (6.5"). If at all possible try to find speaker with 6.5" bass drivers, or if you have space and get lucky, speakers with 8" bass driver.
Though there were only around for a short time, the Diamond 121 (5" and the Diamond 122 (6.5") are worth keeping an eye out for.
There may even be older version of the Wharfedale Diamond available. The Diamond 9.1 is a 5" and the Diamond 9.2 is a 6.5".
You might try the Bowers-Wilkins 600 Series, they have also been around for generations, and should be available in both 5" and 6.5" versions.
Shopping for used speaker is something of a Crap Shoot. You are at the mercy of the seller and how honest he is. And you are at the mercy of your ability to judge equipment.
Though well beyond your budget, here are some speakers that seem to do a lot and sound good.
The Tannoy Mercury is also several generations old, and there should be models for each generation or series available used.
Mission has a long history and there should be several variation of the Mission speakers available.
Edifier R2000DB Active Speakers - RCA AUX, Optical In, Bluetooth, Remote Control - £212/pr -
https://www.amazon.co.uk/Edifier-R2000DB-Bluetooth-Bookshelf-Multiple/dp/B07CHQM8B7/
R2000DB Bookshelf Speaker With Bluetooth, Optical and RCA Inputs
Yes, I know, that's a lot of money, but it is also a lot of speaker. The Optical in allows you to connect digitally to a computer or to the Digital Output of a TV. The RCA Aux allows a direct connect to any Smart Phone, Tablet/Pad, or Computer, and Bluetooth allows you to stream music directly from your Smart Phone, Tablet/Pad, or any Bluetooth enabled device.
There is another variation of the Edifier that would work better if your desktop space is limited -
Edifier S350DB 2.1 Speaker system, Aux, Optical, Bluetooth - £249/set -
Edifier S350DB Bookshelf Speakers With Subwoofer
https://www.amazon.co.uk/Edifier-Bookshelf-Subwoofer-Bluetooth-Wireless/dp/B077Y6PHKQ/
Again, well over you budget, but pretty sweet speakers.
I think what you really want is a budget about 5 TIMES Bigger. Though sadly we all know and understand lack of funds; we've all been there.
Steve/bluewizard