These are two revelations found in the nature and lunar mysteries, both entries say "This animal functions as a druid’s animal companion, using your oracle level as your effective druid level." But does that strictly allow me to qualify them for things that require you to have an animal companions?
Specifically, http://www.d20pfsrd.com/feats/racial-feats/celestial-servant-aasimar/
This feat would change them into a magical beast, which in turns opens up more feat options in my DM's game that might be interesting to me.
Yes, an oracle with one of those revelations does count as having an animal companion.
Does that also mean that at 7th level the animal in the case of primal companion grows to Large size?
if they are picking an animal that goes large at 7 yes. It's in all ways like the druid's.
Thank you