DO NOT turn your OEM steel brake drums unless you can find someone with an old brake drum GRINDER.
If you are lucky enough to find such a grinder, you will need to have the new shoes cam ground to work properly with the increased ID drums.
Finding someone equipped to do this will be equally challenging.
Aftermarket drums are cast iron and are known to be crack prone.
I would thoroughly sand your existing drums with VERY course sandpaper and replace them.