well actually from what i can find its the commonly used
switching diode in japan.. other wise a commonly used diode
like we use here the 1N914

however i can not find an actual
physical lay of it so i don't know if its a SMD or not..
in any case, here is a location that just happens to have it in the
spare parts like if that helps you any.
http://printer-spare-parts.com/partpageW-page21.htm
P.S.
the number is
1S1588 not IS1588
