The blade seems from Kunishige line from Bitchu. In the text are some hints to Bitchu line:
Could be this one,from Sesko:
KUNISHIGE (国重), Shōhō (正保, 1644-1648), Bitchū –
“Bitchū no Kuni Mizuta-jū Ōtsuki Ichizō Kunishige”
(備中国水田住大月市蔵国重), real name Ōtsuki Ichizō (大月市蔵), younger brother of the 5th gen. Kunishige, he
signed first with Kuniyoshi (国吉) and received on the 15th day of the twelfth month Shōhō two (1645) the honorary
title Yamashiro no Daijō (山城大掾), he also worked in Inoo (猪尾), in Matsuyama Castle (松山城), in Azae, and in
Edo, there exist gassaku works with Tameie (為家), after te death of the 5th gen., he raised his own son-in-law to become
the successor and 6th gen. of the main line, jō-saku
could also be:
KUNISHIGE (国重), Jōkyō (貞享, 1684-1688), Bitchū –
“Yamashiro no Daijō Minamoto Kunishige”
(山城大掾源国重), real name Ōtsuki Denshichirō (大月伝七郎), student of Ichizō Kunishige (市蔵国重), he also
worked in Edo and in Tsuyama (津山) in Mimasaka province, itame mixed with mokume, notare, gunome-midare
the first one is higher rated.