Stonelord Pally and his / her Elemental Pet

[That Porter Kid]

Hey guys, i have a quick question relating to the Stonelord paladin special ability Stone Servant

Stone Servant:

Stone Servant (Su): At 5th level, a stonelord may call a Small earth elemental to her side, as a paladin calls her mount. This earth elemental is Lawful Good in alignment and possesses the celestial template, and it increases in size as the stonelord gains levels, becoming Medium at 8th level, Large at 11th level, Huge at 14th level, Greater at 17th level, and Elder at 20th level. This ability replaces divine bond.

So what items can i put on this guy? It is smarter than a mount with an int of 4 which goes to 6 at 11th level (which is smarter than most barbarians].

According to this other post Stonelords Earth Elemental Stone Servants that just treat it as the improved familiar elemental, though nothing in the text supports this. If we go by exact words, we treat it as an earth elemental that can be called like the pally mount. For a awesome class perk it didn't feel right to short-change the companion by calling it an improved familiar with just a next slot. I figured that it should be treated closer to an Eidolon in regards to what items it can use. It cant activate but has all the slots available a humanoid.

[That Porter Kid]

Oh i forgot to add that this is PFS so the home-brew route won't work for this one.