Or you can go to a Raidoshack. They will have everything you need. Don't waste your time mounting your gizmo in a decoy. The ones mounted in decoys are made to attract hunters not birds.
Look for a small motor about the size of a asprin jar. I don't have a part number or name. It is about the size of a small jar with a shaft comming out one end. It will run for a week with a foam wing attached to it.
Or buy a 15 dollar remote controled can and take it apart. That way you have a remote on off switch.
I never hunt ducks, I primarily bowhunt for deer, but I need something to hunt after I bag Mr. bighead each year. Last year I bought a couple dozen canada goose decoys and started hunting geese. There are thousands in the area I live.
I can't call worth a shit, all I can get is the hail call so they do turn and fly by me, but I can't get the cluck down. So they keep right on booking. Occasionally some fly right in to my dekes.
I want all the help I can get. The radio shack way was the method I was looking for. If I wanted to spend $50 for a kit, I'd buy it from Cabela's.
I took one of my kid's remote control cars apart and I think it will work, I could screw the whole car into the deke and use a rubber belt on a tire to turn the wings, but it makes so darn much noise with those little gears, I wouldn't stand a chance...