Here are some costings for the fabrics I use:

Linen Oyster: Half a meter £8.81 ('Take a walk on the wildside' cushion)

Tudor Cotten Linen: Half a meter £6.00 ('Take a walk on the wildside' cushion)

Cotton Satin: Two and a half meters £16.00 (3x60 by 60 fabrics and two 'All American' cushions)