I have the same unit. I recently installed new 7 leaf springs. Mine had 6.
Trailer Leaf Spring | Double Eye | 7 Leaves | 3,500 lbs. Capacity
SKU: MTS-054 from Truck Spring in Saginaw, MI
2018 North Point 377RLBH, Roadmaster Comfort Ride, Dexter E-Z Flex Suspension, Flexair 21k Pinbox
2017 Ford F350 Lariat CC DRW LB 6.7, Air Lift 7500XL with Air Lift dual channel wireless