What make and model hub?

Your hubs may simply need to be serviced (cleaned, new grease, adjustment), but you will have to open them up to find out.

If the bearings are "loose," they're cheap and easy to replace; your bike shop can quickly measure them if you don't have the tools to do so.

Cones are usually pretty durable, and I think it takes a lot of abuse/neglect to damage them. Inspection and a good cleaning may be sufficient. If not, depending on your hub your bike shop may be able to find suitable replacements.

Most difficult is replacing the whole hub. If you don't find a hub with the same build measurements, you would probably have to replace the spokes as well, plus the price of the build. Then you are probably near the price of buying new wheels anyway.