Swapmeets are a likely source of handles. Take a sample as there are millions of small variations.
I don't know where you live but the Bendigo swapmeet (biggest in Aus) is on next weekend. (This w/e is Yarra Glen HCVCA Annual truck show)
I have my shoulder to the wheel,
my nose to the grindstone,
I've put my best foot forward,
I've put my back into it,
I'm gritting my teeth,
Morris, I was at the Pegasus Swap Meet recently and didn't see anything suitable, but did pick up an Inter C series headlight bucket with bracket.
DNO I've had a look online but have since found another way of finding the right parts. Old Mate at work is building a 1940 Ford and suggested TCR components in Bayswater who have lots of door handles and window winders for sale and I can have a look prior to purchase.