Is there any way to gain smite good without taking different class levels?

[Draconi Redfir]

So, i'm taking part in an evil campaign at the moment, playing as a War-Master (http://www.d20pfsrd.com/classes/3rd-party-classes/super-genius-games/war-master) and acting as the party leader/tank. Near the end of the last session, our party found a +1 Dastard (http://www.d20pfsrd.com/magic-items/magic-armor/magic-armor-and-shield-special-abilities/dastard) full-plate armour. We have no anti-paladins or cavaliers, and I’m the only one who can wear full plate armour anyways, so i swapped out my regular +1 full plate for some cash and put on this new set. It looks nice, but right now it's not really doing a whole lot.

I COULD take one level in Cavalier or four levels in Antipaladin, but then i wouldn't be advancing in the war-master class and my sub-par abilities wouldn't be getting any better. Do any of you know any ways that i could potentially make use of this armour without taking levels in a new class? We're level five right now, moving into level six. Are there any feats or items that could potentially give me the smite good ability or a half-fiend template or something?

Thanks in advance for any help you can give.

[Extra Anchovies]

Tieflings have an alternate race trait that gives them a 1/day Smite Good in exchange for fiendish sorcery and the SLA. They're not on the Reincarnate list, though, so you'd need some sort of DM-arranged ritual (á la Savage Species) to become a Tiefling.

Really though, it's +2 AC against one creature at a time, probably only once per day. Unless you want Smite Good for other reasons, I recommend letting the property go unused for now. Maybe you can sell it to an antipaladin for a pretty penny down the road.

[Spore]

The armor enchantment while lorewise is absolutely awesome is mediocre at best. It is only really good on full classed Antipaladins (Cavaliers charge too much around, single level AP doesnt have enough Smite Good) that stack armor class (and even then a +2 FP would probably be just more useful, as would a Mithril FP be).

If the armor is definitely not more than a Dastard armor sell it but not for its market value. If you sell it for half price you get 2.825 GP. If you buy a regular +1 FP you pay 2.650 GP. So basically you sell a bonus you cant use for less than 200 GP. If you have looted said armor from a foe it is clear that any forced of evil tend to try and kill you. Maybe supporting them with powerful items 200g a pop isnt such a good idea. And maybe you can ask the vendor if he can sweeten the deal for you a bit. A few potions or a simple wand come a long way.

Buuuuut if the armor is showing more potential maybe go for its corrupting powers. My old DM prepared a few ritual based artifacts for us that allowed us to unlock certain powers after certain rituals (and levels).