Akai S1000 / S1100 samplers

Hi everyone.  I am new to the forum, and have a quick question, 
please.  

I just won an Akai S1000HD on Ebay, and it should arrive in a few 
days.  The amount of RAM in this unit is currently 16MB.  I wonder 
where I can purchase the RAM expansion cards to fill it up to the max. 
(I think it's 32MB)

Thanks for your help...  Gary