That's a tough one. There are LED replacement fixtures, but to cover the same area you'd need a very expensive one.
MH lamps should not bust easily, so you have to make sure the lamp and the ballast are a match. If the ballast is for a bigger lamp, yours gets an ass whooping every time it starts, dramatically diminishing it's life.
For large areas, MH will provide the most efficient way to light the lot up. But make sure the fixture and lamp are a perfect match. There are LED replacements, but those units cost an arm and a leg. Cheaper China alternatives will be more expensive in the long run, because they don't run efficient, and fry a lot because of poor thermal design.
My 2¢: get a replacement MH lamp. Maybe adjust your lighting schedule a little to keep the lamps to live longer; less starts per day, and keep lighting hours to a minimum.
Good luck!
