replacemant ballast

[Douglas]

I'm looking for replacement ballasts for my giesemann Infinity 2x250-4x54watt T5's. Came home to one blown light. Checked bulbs, and power supply, and have determined it's one of the ballasts. The problem is, they're both different, and one powers the T5's.....so i may need a set. Any ideas on where i might aquire a set that will be compatible?