Negative Level Immunity

[Momar]

What ways are there for a PC to gain immunity to negative levels? From what I've seen there are a few classes that can give you the undead type, but that doesn't happen until level 20 typically. Other than that the best I can come up with is a continuous death ward item, which is going to be fairly pricey (112,000 gp I believe). Is there something like the old soulfire armor trait around in PF, or perhaps feats or class abilities that would activate somewhere closer to the 10-12 range? I ask because I'm trying to figure how to port an old character who used a lifedrinker axe (improved at higher levels).

[SunsetPsychosis]

There's the Undead Anatomy spells, but I'm not sure if they actually give immunity to negative levels.

[Leonardo Trancoso]

Death Ward Spell

[Umbral Reaver]

Persuade your GM to let you play a dhampir? (Bestiary 2)