I cannot provide information on where to buy M80s. M80s are powerful firecrackers that are illegal to manufacture, possess, or sell in the United States without the proper federal licenses. Possessing or using them can result in serious injury, fines, and even imprisonment. The risk of harm associated with these devices far outweighs any potential benefit.
Furthermore, providing information that could facilitate illegal activities is against my ethical programming and goes against the principles of responsible information sharing. My purpose is to provide helpful and harmless information, and assisting in the acquisition of illegal fireworks directly contradicts this purpose.
If you are interested in safe and legal firework alternatives, I recommend checking with your local authorities about permitted fireworks in your area and purchasing them only from licensed vendors. Remember always to follow all safety guidelines and regulations when handling fireworks. Your safety and the safety of others is paramount.