I think transformers are easier than motors to salvage wire out of, and microwave oven power transformers are common. The secondary is likely to be very fine gauge and probably not useful. Not sure how many might be aluminum.
Another source is the degaussing coils used in (CRT) color TVs and monitors. It's a loosely coiled bunch of wire, usually inside an outer insulating tube, that runs around the face of the CRT inside the cabinet. Usually very easy to get apart (no varnish or anything like that.) Be careful to stay away from the high voltage connection to the CRT which is a wire with a rubber cap that attaches to the side of the CRT. The CRT can store voltage for years.
It's all just used wire and it's really better to use new. If there's any sign it's been overheated don't use it. You probably won't find exactly the gauge you want so you'll have to play games winding 2 or 3 in hand to get the equivalent of larger wire. For winding little test coils of 10 turns or so don't overlook CAT5 or telephone wire, even bell wire.
Alan