Name/style/model for this brake spring?

It's called the spring or return spring for a side pull or side pull caliper brake. A replacement is usually found by searching for the maker and model of the specific brake.

Finding a replacement will be tough. The complete brake mechanism is very inexpensive making the individual parts so inexpensive they aren't worth keeping in inventory.

Criggie is right, using two pliers or a vice and one plier twist it back into the correct shape and use it.

Springs are supposed to be made of spring steel known for it's ability to be bent and return to it's original shape. In spite of it's ability to bounce back it can be bent in such a way as to hold a new shape.

In your case you need a very small adjustment that should not impact the spring characteristics of the metal.