Most of the newer Scanners with the updated Firmware will handle Narrowband.
Try and enter it and see what your Scanner does. The older Scanners should round it off, and if you are close-enough you should have no problem still hearing them
Narrowbanding doesn't change the frequency it narrows the bandwidth. Just enter that frequency as usual. Any reception on that frequency may be reduced due to the narrowed bandwidth. There is nothing you can do about that.