I found my luggage rack by running a perpetual "Followed Search" on Ebay. It has taken a year or so once or twice and I have had to give up when the bidding was going past $220 - that, was insanity. Typically, I spend 50-70 bucks or so.
But eventually, a luggage rack will show up on Ebay. All of my Honda bikes now have racks if they were not originally equipped with racks and I have found that a company called "Triple-A" made the best of them back in the 70's. The chrome was good and the rack will be embossed with the names of the bikes that the rack fits.
Rick