Extend flat cable between LCD panel and driver board
Flat Flex cables used with LCD panels are usually custom-made, and sometimes even carry some components like filtering caps and resistors. I'm pretty sure they don't sell such cables with a custom length. You could order custom cables to be produced, but that only makes sense if you need hundreds of them. So no, I don't see a way to achieve this in a hobby project like yours.

Edit:

The link you have provided in comments shows an LCD display which seems to use a standard FFC cable. If this is the case, you could buy such LCD with an extension cable, then buy a longer extension cable. Standard FFC cables are commonly available up to lengths of 500-600mm, you may find a longer one if you're lucky. Of course, Tom's comment still applies: you may get a reduced image quality, visual artifacts, or a non-working display when using a long extension cable, but it's worth trying.