According to the ISMACS listing
Serial numbers K317001 through K337000 was a 20,000 unit build order of Model 15's that was begun on June 23rd, 1902. The next order for 15's on the K listing was August 15th. This machine would have been built between those dates.
EDIT: for a Model 15 to be worth $100 to ME it would have to be in pretty good shape.