A small charcoal grill, like a baby Weber with short legs.
Aluminum clothes dryer flex ducting. 8 feet
Aluminum (real metal) duct tape
A large, heavy duty cardboard box
An electric hot plate
Thermometer
A small cast iron skillet with lid
Set the box up on a picnic table, and the grill on the ground.
Tape one end of the flex duct over the lid vent of the grill.
Tape the other end to a hole at the bottom edge of one side of the box. Position the box normally, the the open end up.
Run the hotplate cord out the bottom vent of the grill.
Place wood chips/or pellets in the skillet, cover it, place it on the hotplate, put lid on grill.
Place venison on rack in smoker, with drip pan underneath.
Plug in hot plate. Watch smoke flow.
Crack open box top to allow airflow.
Stick thermomete through box at meat level to monitor temperature.
Commence to smoking. ==============
Watch out for wind. Secure the box if it's windy.
Not too close to house, in case box catches fire. Watch box constantly for this reason.
Works best for real cold smoking in winter, or cold weather.
=============
Just curious, are you curing the deer leg into ham before cold smoking? It's not recommended to cold smoke uncured venison, because the parasites won't be killed, or the meat cooked.