Window balance spring

Most balances can be replaced, but it depends on the make of the balance itself. I'd be happy to advise you further, but I'll need more photos to get started. Please let me know if you can show me a few shots of the balance in question.

Note that I may ask for more photos after that, but I need to know what to ask for, first. Consider these preliminary photos to give me an idea of the kind of hardware you're working with. Then we can focus on the important details.