FlexBilt Customs offers this DIY Rear Leaf Suspension Block Kit that fits 2006 or newer Ford F-150, 250, or 350.  This kit includes everything that is pictured and labeled below:
 
12 Inch U-Bolts Measure: 0.55" x 0.06" x 3.25" x 12.00"
Fits:  2006 & Newer Ford F150, F250, & F350
 
Kit Includes:  
(2) Shims
(2) Shock spacers
(2) 2" Blocks
(4) M14mm x 1.5mm x 82.55mm x 305mm U-Bolts
 
Specifications:
Block Material:  Aluminum
U-Bolts Included: Yes
Axle Tube Diameter:  3 inches or 76.2 mm
Block Thickness:  2 inches or 50.8 mm
Shipping Weight: 16.2 lbs
Package Dimensions: 14x4x6
 
* Only a few left in FlexBilt's stock