I'm looking to make a ceiling fan out of an old propeller. Does anyone know where I can purchase a suitable motor, like an Emerson K55XL?

Wouldn't that be kind of dangerous, using an old propeller ?

It's not much different than standard ceiling fan blades. It's a wood propeller with two paddles.

eBay, I suppose. There's a parts supplier online that sells NOS GE stack motors similar to the K55 but I don't remember the link.

Have you tried Lowe's? They do not stock this kind of item in there stores, but I am pretty sure they can special order almost anything. Go to the commercial sales desk and ask for assistance

Lowe's won't have this type of part.