To get magmotar, you have to get a magmarizer which is at route 214 and trade while holding it. It's pre-evolution is magby which you have to breed magmar or Magmotar to get.
For Electivire, you have to get a electrizer at valley windworks and trade with electabuzz holding it. It's pre- evolution is elekid which you have to breed Electabuzz or Elctivire to get.
Hope this help =)