His pedigree...
http://www.pedigreequery.com/gun+bow
He was sent to Japan after 8 years at stud in USA, it states .
I find that Harlan's Holiday
http://www.pedigreequery.com/harlans+holiday and
Menifee
http://www.pedigreequery.com/menifee2 have Gun Bow in the first 5 gens of their pedigrees due to both having the same sire , Harlan . It appears that Menifee was sent to Japan also . So to cross Gun Bow HH is the only one left standing in the US .
How about some mares with Gun Bow ?