Controlled impedance boards --- cheap? suppliers???

My next board will have to function in the stratosphere (20 GHz), so I’d like to find a reasonable (batch?) pcb supplier who uses Rogers substrates. Delivery time is not an issue. Price is.

Any ideas? Just for reference, the apcircuits quote generator gives me over $300 for a one inch square board.

Not sure if Rogers 4350B is OK at those freqs, but Gold Phoenix has it. Not cheap, but they list it as $250 for 100sq in or $260 for 155sq in

http://www.goldphoenixpcb.com/singlepag … ecialprice

/mike