Sales at Maine’s fireworks stores have far surpassed initial projections when the devices became legal last year for the first time in 63 years. When legislators debated a bill in 2011 seeking to legalize fireworks, the Maine Revenue Services estimated that stores would generate about $120,000 a year in sales taxes. In reality, the state collected $380,000 in sales taxes for the latest 12-month period ending May 31, according to the agency. With a sales tax of 5 percent, that means fireworks stores had sales of $7.6 million in the past year. The original projections were somewhat conservative since fireworks were new and there was no baseline from which to work, said Maine Revenue Services spokesman David Heidrich.