Specialty wood drilling/boring bit

I built a timber frame house many years ago and used homemade steel connectors that were hidden inside the beams. I connected the beams to the posts with 1/2" bolts. In order to hide the bolts, I used a standard 12" long by 1/2" diameter twist drill with a 1 1/2" forstner-type collar that attached to the 1/2" bit with set screws. This allowed me to drill the 1/2" hole completely thru the beam and bore the 1 1/2" hole in about 1 1/2" on one side, then using the 1/2" hole on the other side as a guide, bore the second 1 1/2" recess. I was then able to use standard washers on both ends of the bolt and cover the holes with 1 1/2" dowels. I would like to do something similar using round wood and star-type timber washers. Does anybody know where I can get this type of boring tool? It is essentially a flat faced forstner bit with a 1/2" hole in the middle that is secured to the 1/2" bit with set screws.

This is one of the only places I know that still has these

https://www.dictum.com/en/tools/woodworking-metalworking/routing-drilling-tools/wood-metal-masonry-drills/forstner-bits/707044/fisch-countersink-o-50-mm

Hope that helps, nice that you are going 1/2 because these are metric....

Thank you very much, Chadwick!
RWC

You are welcome! I thought you might like that!!!