If this is the one you are asking about it is good. I use it with six standard 42 pound weights, i see no reason why it wouldnt work with the larger ones. $130 to your door vs the authentic "heavy hitch" version for $320 lol they do the exact same thing. I modified mine a little to carry the bxpanded tray.
I’m sure there are a lot of sources. I purchase suitcase weights from local John Deere dealer. Sometimes Lowe’s will carry them too. Always found it cheapest to pick them up locally, dealer or otherwise. Sometimes you can find them on Craigs list too