There are endless good mechanical options.

But if 650£ overall is too much, forget it.
I know you said it for transmission only.

You will spend about 2000 for a decent motion system, and about 2400 for an excellent motion system, for a full-sheet setup.
For 2k you can get excellent ac brushless servos, and should do so, and forget anything else, for a business venture.
Rotating 2.5 m ballscrews with modern 220v ac brushless servos is trivial.
They will provide theoretical accuracy around 2 microns, 0.002 mm, and speeds higher than you want to use.

I use about 1/3 of the max speeds available on my large vmc for cutting metal.
Table is 200-250kg, bridge is 500-700 kg, a 400W servo is ok (marginal) but a 6 Nm servo (750W) runs it all day long.

Woodworking loads are under 100 kgf.