Have you all found this website? https://iplan.townplan.gov.my/public/geoportal

Under “Lapisan Sokongan” icon, choose “Lain-Lain” then “Sempadan Bandar”. That maybe what you want.

However things in Klang valley is not as straight forward now as before. Where before you have pekan smaller than bandar, smaller than daerah. Now we have bandar/bandaraya bigger than daerah, and bandar/bandaraya going over more than one daerah.

One thing for sure, boundaries for Daerah and Mukim in Malaysia, have not changed since before merdeka. However, boundaries of Majlis Perbandaran, Majlis Bandaraya have been changing over the years.