We can't readily answer your questions.
Are you to replace the whole window unit (frame and sash) or just the sash? There are different kinds, models, designs of sashes and frames, so a price would depend on a unit's or sash's features.... single pane, double pane argon gas filled, etc., etc. Replacing a whole unit depends/may depend on whether your home is wood frame, brick, stucco, etc.
I suspect you will be replacing just the sash. There are replacement sash kits, specific for older homes, but companies can make/replace any design of sash. Usually these are custom made (but not always necessarily so). Many window/sash units are standard size, so a custom build may not be needed.
Kolbe and Kolbe (I think this company is only Kolbe, these days) makes custom windows and sashes, and has replacement kits.
Pella has replacement window and sash kits.
Mayfair makes less expensive units.
There's likely a local shop that makes units, as well.
You can get estimates from all those places.... I'm sure they have representative offices/outlets in your area. Let them come out and measure your present windows. They know how to measure, properly, for the proper replacement units or kits you would want/need. If your frames are in good shape, all you may need to replace is the sash, not the whole unit.