The Yamaha R3 is a good though a little dated - option if you’re looking for a sport bike in this class. It’s now even more appealing after the recent price drop post GST 2.0.
Another solid choice to consider is the KTM RC 390. Despite using the older 373 cc engine, it’s still a fast, capable, and exciting machine to ride.
If you’re open to stretching your budget a bit, take a look at the Kawasaki Ninja 500. It may be quite expensive for its class, but it’s a sweet, capable, and reliable bike that can serve you well for many years.