I Googled your part number and it returned 4 pages of links, these three appear to sell the part number you specified. Is there some reason a substitute will not work? These SIPS are generally pretty generic, either common to one pin or all seperate. Mouser does indeed sell resistor networks as do many others.

http://www.hkinventory.com/public/Of...t4=0&datecode=
http://www.partminer.com/pagedetail/5300/11
http://www.accordtech.com/comp18_19.php