I am replacing them at a rate of .2 per machine year. I get them from
Quement Electronics in San Jose (408) 998-5900. (I get them there because
they are < 1 mile away from me).
Hope this helps.
Kevin Kelleher (408) 559-7778
Xilinx Inc. {pyamid,uunet}!xilinx!kevin
(I have no releation to Quement Electronics).