I have to put a new cord on an antique fan. I wanted to use a cloth covered 3 wire cord to add grounding. Any sources out there? So far I found one at Grand Brass but it has a modern looking cord cap on it, which I will use if that's all that is available. The two wire cord caps look original but I don't want the liability since it is not my fan.

http://www.lampsandlights.co.uk/flex.php

Probably not going to like my answer, but grounding plugs are never used in the restoration of these fans, even the ones sold publicly by members of the AFCA that professionally restore them, and by specialty companies like VintageFans LLC.
When it comes to history, the NEC can cram it and take a hike, IMHO.

A polarized plug is plenty of protection for these fans.

ht tp://www.vintagefans.com/

http://www.fancollectors.org/

By Vintagefans:
Note 2-wire cord



Mind telling me what fan you have?

It's just a GE, 1942 I think. I don't have the model number, the fan is still at the customer's house.

40s!?
Twisted cloth cord was long gone by then!
Neoprene rubber cord was introduced on most appliances in the early 30s, including fans. Clothes irons and a couple other similar items kept their asbestos-insulated cloth cords.