I have a 6' Lucknow blower that is very well designed and constructed. Built like a tank. Other brands that look well built to me are the Farm King, Allied, Buhler blowers. I frequently see the Farm King, Allied, and Buhler names hyphenated, so they may be made by one company or manufacturer. Anyway, they all appear heavy duty.
A 7' blower is certainly within reason with your machine, but I would consider whether a 6' blower may be a better choice depending on your tractor width. imho, the blower is best sized to cover the footprint of the tractor plus a couple inches. For my use, the 6' covers my width and is about perfect for one pass into a driveway, and one pass out.