Source for speaker cloth?

[AudioFeline]

You could visit Spotlight or another fabric store to see what they have in stock.

There are sellers on eBay which specialise in guitar amp speaker cloths, which have interesting and less common weaves available, many in a traditional style.

Spotlight? I was under he impression that is has to be special cloth so as to have a flat frequency attenuation spectrum.

I have no clue what is needed as I do not even have any sample.

Or do you mean that one should not worry about that and just get something that looks nice?

The cloth needs to be special in a few ways. It shouldn't be too thick/heavy, so it doesn't absorb the sound. The weave should be quite open, so the sound waves can travel through (this is easy to test - how much light can pass when it's held up to the light?). Finally, it needs to look special, and to be compatible with period cloths and the style of the device it's attached to.