You should just buy one of these,,,
https://www.youtube.com/watch?v=xEpYQMdnxHY&t=20s
I doubt anyone is ever going to load more than 50-100 .500 Linebaugh's in one session so setting up a 550 for it would be a waste of time. I can easily load 50 .44 Magnums on my Press in 1 hour, and you can use anyone's dies you choose. Have a look and see just how easy this is. Loading .500 Linebaugh's would be done exactly the same way as in the video above.
This tool will load just about any Brass Cartridge below .50 BMG, and I have one guy who loads .577 NE by the campfire every night in Namibia.
Randy