Additionally, should the replacement charger have a lower amperage rating, I believe that your charging time could be extended.
Why not repair the original charger? That would be a great low-level, fun, learning project and we would be glad to talk you through it. It is most likely a very simple problem... My bet is, in order of likelihood, a bad fuse, a bad cap, or a bad diode... There are other possibilities, farther down the list...
What is your interest in doing that? If you might give it a go, what is your skill level and what equipment do you have access to? Most likely you would only need a Multimeter and a solder iron/supplies.
Come on, let's do it! Start by unplugging it and opening it up. Hint - Screws are often hidden under labels and rubber feet.
Give it a good look, but there is no need to do anything else, yet. The problem may be readily apparent. Look for scorch marks and swollen, leaky capacitors. If you don't see the issue, we will tell you what to do next.
Pictures would be most helpful, please and thank you.