Definitely a kit but still nice & expensive! 550s did have wide 5 bolt pattern & drum brakes. Stickers on roll bar make it Look like “it’s been there done that though”. The real ones are about as rare as hen teeth too.
There’s a company in England that makes a “kit” that uses the original drawings, substituting glass for aluminum. They also make 5/4 kit (just a little bigger for 6s). Prices for kit less running gear $25+K
