Because of the ever changing US Dollar always email or telephone 
us here at RCS Radio, for the latest price at the time.

Note: at RCS we only sell it in 18" x 12" panels (that is 8 standard
guillotine cutouts from a common 4' x 3' sheet , and we will cut this
up for free, from a 18" x 12" (450mm x 300mm) into any simple useable
raw blank circuit boards.  (but please, no cake decorating sizes)

But as a guide, 
Single Sided will sell for approx $10 to $11 per square foot 
and
Double Sided will sell for approx $15 to $18 per square foot

this is based on common industrial 1/16" (1.5mm) thick substrate
and using 1oz copper per square foot or 35um (35 micron thickness)