I'm using these 'off the shelf' track clamps to mount the curtain track as they match the track I'm using and look well made. Just 2 would be needed for each meter of track.

I purchased a set of 20 of rollers on eBay for just £6.15 delivered. These are too wide to fit inside my track though, so I'm going to need another solution.

To get the exact size pulley required with the right number of teeth, I designed and 3D printed them.

I found a supplier of HDT5 drive belt and bought a 3m length. This belt is 9mm wide.