Don't know if the price will go silly in the last moments, but I would go for that at three or four times the current price.
Not very familair with that particular model, but Maico did a 350 version called the Taifun. Cycle World did a road test in the '50s of the Taifun - I have a copy that I got from the Automobile Museum that used to be on the top floor of the car park for (IIRC) the Imperial Palace complex on the Strip in Las Vegas - the one and (so far) only time I have visited Vegas & that was 30 years ago. Still got the magazine in the loft somewhere.
Don't think that many were made & also don't think they made it to the UK, as protectionist import taxes at the time made foreign bikes prohibitively expensive & IIRC the Maico was a premium price to start with.