$200 is a very reasonable price on the GJ particularly since the pandemic has driven up the price of bikes. It's likely somewhat on the large size for you but do a bit of reading on "French" fit. I'd buy that bike and then post some questions here about how best to fix it up. It's great bike. I have a Motobecane Grand Record the same as at that GJ and it is very good riding bike.
By the way, the rear derailleur and shifters have a value in the used market.