OEM hitch with 36" extension?

I would go with the following:

Curt Trailer Hitch Receiver - Custom Fit - Class V XD - 2" $245
Specs:

Receiver opening: 2" x 2"
Rating: Class V
Maximum gross trailer weight: 17,000 lbs
Maximum GTW when used with weight distribution: 17,000 lbs
Maximum tongue weight: 2,550 lbs
Maximum TW when used with weight distribution: 2,550 lbs
Limited lifetime warranty

Curt Hitch Extension and Reducer for 2-1/2" Trailer Hitches - 24" to 34" Long $134
Specs:

Application: 2-1/2" x 2-1/2" trailer hitch receivers
Receiver opening: 2" x 2"
Extension length:
24" From center of hitch pin hole furthest from edge to center of hitch pin hole
34" From center of hitch pin hole closest to edge to center of hitch pin hole
Weight capacity when used with 24" length:
Maximum gross trailer weight: 6,000 lbs
Maximum GTW when used with weight distribution: 8,000 lbs
Maximum tongue weight: 600 lbs
Maximum TW when used with weight distribution: 800 lbs

Weight capacity when used with 34" length:
Maximum gross trailer weight: 4,500 lbs
Maximum GTW when used with weight distribution: 6,000 lbs
Maximum tongue weight: 450 lbs
Maximum TW when used with weight distribution: 600 lbs
Limited lifetime warranty