You can buy an Aloris AXA -- and without a doubt you would never regret it, but in my case this would cost more than the lathe itself. So I went with a nice post made in China. A recommendation is the Enco 100.
I am virtually certain that I bought my setup from Shars
They sell extra holders of various sorts. I ordered three that are marked 250-101 in 2020. These will cost me $20 each once I include shipping.The best thing about a quick change post is that once you get a cutter in a holder and set the height, you can just pop it in and get to work. Just having one holder, and having to swap tools into it sort of defeats this convenience (but saves money I guess).
Tom's home page / tom@mmto.org