Admittedly, I've had perhaps more than my share of parts cars over the years; regardless, a brake drum is something I've almost never had to replace. On the rare occasion that I did have to replace, I would find a good used one from my stash. At worst, I might have to have the drum turned.
Where I live (in the USA), we have a really great local auto parts store. Granted, it caters more to American cars, but until sometime last year -- when their lathe broke and parts were no longer available to repair it -- they routinely turned drums and rotors. But most modern car drums and rotors are simply not worth turning; rather, they seem destined to be as much a throwaway item as the shoes or pads that rub on them! And it would appear that current aftermarket replacement drums and rotors for our cars are of about the same quality.