That IS interesting, if it did not have CELO formed on the seat stay top eyes, I would have thought that someone placed Celo transfers on a Japanese bike.
I would not bother repainting it, just arrest the rust as mentioned previously.
The saddle looks whacked, it might be possible to align it but the cover is compromised, the handlebar tape problem is minor in the scheme of things.
The guy from the bike shop probably thought it was one of the Colnago sourced bikes too from the initial CL images. DiabloScott's archive really is definitive of what Marcel was doing, but not the Japanese importation.
Creative.