I have no idea what a transfer is worth. However, I sold my loose takeout sliding around in the back of the truck unknown working condition deuce Spicer 3053 transmission for $100 a couple of year ago. I think the buyer liked the price and I didn't want to lug it around anymore, so it was win-win.
How much do you have in it? Price it according to what you need to get. Maybe it's low, in which case you might out a fellow SS'er. Or maybe your price is high in which case it won't sell so you'll lower the price until it does sell.