The oil ring is a one piece design might be hard to find that style.
I'd like to keep this thread alive for awhile, as I'm also pursuing early style 80mm ringsets.
TLCbobber has a point about the deck height. Here's a pic of 447 piston dimensions. You'll want to confirm dimension "E". Also, confirm the diameter of your pistons. Are they 80mm?
...Just been to check the rods on my old crank, they're marked 533 ...