New would be good, but quite expensive. I would contact someone like Henderson and get some figures.

http://hendersonproducts.com/dump-hoists.html

If you can find a used one including the subframe, pump, reservoir. ram etc. it would probably be much cheaper. I removed farm beds from several old trucks and made truck tractors out of them. I think I sold the dump equipment for scrap iron. It is one of those things that when you have it, it is scrap iron. When you are looking for one it is hard to find. Several years ago old farm trucks sold in the Midwest for about $1,000 and they had everything already installed. You might watch farm auctions like this one.

https://www.auctiontime.com/listing...mc?sortorder=63&SCF=False&page=4

Scroll down to the 1952 GMC