Yes, it will work just fine. I got one for my phone a year ago and have not had any problems. You can get a low cost one at discount stores like Wal Mart or Target, or on-line at Amazon. Just make sure to check the plug shape to ensure it's compatible.
Absolutely, you can purchase a generic Motorola charger for your cell phone from any srore. Most chargers are packaged so you can see if it is in deed a good fit for your phone. These types of replacements are always less expensive than a Motorola Razor replacement.
You would have to get one that is compatable with your phone. I don't advise using any other one because it could mess up your phone. That would cost you a lot more money to replace your old phone, if you do.