Checkout www.mobile01.com and do a search of s72, you should find someone who have Benq S72...
http://www.mobile01.com/topicdetail.php?f=159&t=83131
http://www.mobile01.com/topicdetail.php?f=159&t=72765
I think the Mfg Part# for CL56 keybord is #72174530001 which is the same for CL51. Just google the part#. Here is one from the search...
http://www.pc4mecs.com/cgi-sys/mivav...TC-72174530001