Fixed sights.
Three inch barrel.
Winchester .357 Mag. 125 gr Silvertips HP.
In short, a S&W M-13/65.
If price is an issue, a used four inch of the the above is more than acceptable and just as concealable. The four inch also opens up the potential to aquire a S&W M-581/681, "L" frame.
I am not fond of Rugers, but used four inch Speed Six's can be found in any newspaper or pawnshop.
Also note that any of the Taurus line are shining stars for reliability and variety. Professionally I carry their two inch .44 Special.
Other things I would recommend for a serious carry revolver:
Remove hammer spur (bobbed)
Double action only (internal modification)
Grips that fit you (wood, rubber or grip adaptor, etc)
Nothing that requires a battery, repeat NOTHING!
Ankle carry?
Renegade Holsters, Cozy Partner. Elastic based. It can be cinched so tight it will cut off the circulation. They are out of Phoenix, AZ. Sorry, no other details.
Good luck!