Without Flame body Pokemon.
Edit:I also want larvitar's hatching time.Sorry for any inconvenience.I thought I added it when I asked the question but apparently I forgot to do so.
Larvitar 10,240 steps 5,120 with magma armor or flame body
Happiny 10,240 steps 5,120 with flame body or magma armor
Source for Larvitar
Source for Happiny
You could also get O-Powers or Oval Charm to make it faster