Reese 1-1/4-in x 9 x 1-1/4 Drop Ball Mount in the Trailer Hitch Ball Mounts department at Lowes.com
TowSmart Class V, 15,000 lb., 8 in. Drop x 6 in. Rise x 1-1/4 in. Shank, X-Mount Trailer Hitch Ball Mount 7181 - The Home Depot
Trailer Hitch Ball Mount Extension: 12 Inch Extension, 2 Inch Drop, 6,000 lb Rating (9431LAK Same Fit As Part # 9341LAK) - Land Rover tow hitches & accessories from Atlantic British
Class 5 21,000 lb. "X" Mount 5 in. Drop, 3 1/4 in. Rise, 1 1/4 in. Shank Reversible Tailer Hitch Ball Mount - TowSmart
Curt Class 4 Ball Mount (2" Shank - 12,000 lbs. - 6" Drop - 9-3/8" Long) - 45446 - SharpTruck.com
CURT 45507 Vertical Receiver Ball Mount (1-1/4 Shank, 3,500 lbs.)
CURT Class 3 Ball Mount 10 1/4" – Woodland Airstream Parts and RV Accessories Store