Cross referencing Ruger part numbers, it doesn't seem likely (P89 P/N: V03301 to P95 P/N: Q0330). The P90, P91, and P93 use the same rear sight P/N as the P95, so anything for them will work.
As the Millett adjustable rear sight also requires a new front sight, you might want to give these sight sets a look:
http://www.brownells.com/.aspx/sid=2307 ... r_P90__P91
Midway lists the adjustable sights that they carry as fitting the P90, P91, P93, P94, P95, P97:
http://www.midwayusa.com/viewProduct/?p ... ber=665042
http://www.midwayusa.com/viewProduct/?p ... ber=681787
http://www.midwayusa.com/viewProduct/?p ... ber=337969
You could always give Ruger a shout:
Telephone: 928-778-6555 / Fax: 928-778-6633
(Monday through Friday 8:00am - 5:00pm MST)
Regards,
Greg
BTW, welcome to the forums
