Etsy does seem to be a bit more pricey than Ebay but I have only had good dealings on it - as I have on Ebay.What about ETSY?
My Executive (gold Fatboy) was a gift. It belonged to a friend's grandfather. She could have sold it on eBay, but I got lucky.
Still, it was "stuck" on a setting. I had to put it in my ultrasonic cleaner to get it unstuck. That's a common problem with old adjustables, but easy enough to fix.
It's a very good razor!
You can use the Buy-Sell-Trade forum here (BST forum for short). These razors come up often, many of them are in great shape. People have to post decent photos of what they are selling and indicate the condition it's in.