Welcome to DeereTalk! The x55 tractors continue to be reliable, solid, and popular tractors, but parts prices continue to go dramatically up. Several years ago one of my headlights became weak (but not burned out). I was somewhat surprised the replacement price at Deere then was about $25. I bought it but wrote down the number that was on the bulb. It was that same GE H9406 you listed. If I ever need another one I will go to an auto parts store with that number. Interestingly though, the price at your Deere dealer can vary. The current price at my dealer is about $50. If you log on and register at JDparts.com you can see your dealer's price. A while back another forum compared JD parts prices around the country and found significant differences.
Part Number: AM102023
Part Price: 49.87 USD
On Hand: 0 Check Other Stores
Description: HEADLIGHT
Part Number: AM102023
Part Price: 49.87 USD
On Hand: 0 Check Other Stores
Description: HEADLIGHT