Rather than an extender you could just go for a new cable like the one on Amazon basics range, which is 25ft/ 7.6.2m long going for only £11.99.
Iv'e had this cable installed now for a couple of years now with no problems or loss of picture.
Maybe thinking about buying a future proof 4k ready cable could be an idea but at twelve pounds, I'd upgrade at a later date if needed.
I think there is a limit to how long a cable can be without a booster, something to look into maybe before going for the full 10m length.
There's also the splitter box choice, which is a small box with one cable in and numerous cables out, they send the same picture to 4 or more TVs at the same time.
I have the Cablesson version which works perfectly well with no problems so far, you can also find these on Amazon.