I finally found some time to post pictures from the build from this past weekend. The build is now complete, with the exception of hinging the access panel door.
The fluted column cap & base. I bought these at Home Depot, they were originally much larger than what you see here. I cut them down to size with a miter saw, to match what I needed.
The fluted column trim, also from Home Depot, went in between. It hides the exposed plywood cut edge at the corner of the cabinet. I glued these in place and also used 3 or 4 finish nails to hold them in place until the glue dries. Later I'll fill in all these little holes with wood filler, then sand smooth.
Pre-primed wood base, again from Home Depot. Cuts were made on a compound miter saw.