Did you try searching for VW Super Beetle forums, populated with Beetle owers? They're more likely to have answers and experiences to help VW owners maintain VWs. The choke mechanism may be either thoroughly seized and rusted or repairable depending on conditions. Carburetors are 'old school' and you may not have a mechanic familiar with them. No different from mechanics unfamiliar with electronic fuel injection systems. Maybe some penetrant like WD40 can free up the choke shaft. Removing the carb and disassembling rusted, corroded parts may help restore it. Carburetors are all mechanical, unlike electronics in EFI systems so someone familiar with 'old school' carburetors are the ones to seek help.