I don't have any feat to spare.
I think the sentiment here in the thread is that you reconsider that choice.
However, I just gave a player of mine a cohort with 8 hit points at 5th level, and so I'm familiar with items to keep a character alive.
First, you might consider Repelling Gauntlets, from MIC. They work as an immediate action to interrupt someone who is running toward you to attack. As soon as they get near, they must make a Dex save and if they fail they are pushed back 10' and they lose leftover movement.
Similar, although not an immediate action, are the Bracers of Repulsion. They operate like a wave of force, driving anyone near you back by 5 feet. This is very useful when you end up with someone too close, and you know you'll incur an AOO when you try to run. So you blow everyone back, and then run screaming, no AOO.
A Transposer Cloak will allow you to swap positions with an ally. I've used this in combat many times to save a life — the hurt person teleports to where someone unattended stood, while that same unattended person is suddenly in your old position. Generally, this ends up being the cleric. He's off to the side blessing the party or whatever, but he's got armor and a mace, so he's OK to go toe-to-toe with your attacker for a round while you recover in safety.
A Brooch of Stability will auto-stabilize you if your HP drop to -1 or lower. Or you could use the same item slot for an Amulet of Tears, which gives you 12 temporary non-stacking HP for 10 minutes.
Finally, from Complete Scoundrel, you can use the Panic Button items. For example, the Panic Button of Escaping allows you to teleport away as a swift action. It doesn't occupy an item slot, either.