7K to spend on a paladin to make a big impact, what should I buy?

[Itap]

AC/HP items, your job is to stay alive. I wouldn't worry too much about haste atm, since you will be keeping your aggro in groups via spells.

You can get all DW pieces (minus BP and legs) for about 1800-2k. Thats 95 AC. Thats 43 AC more if you replaced the plate pieces with the DW.

Swap out the Crested Shield for a Clay Guardian, 25AC + 50HP for around 500pp.

Pick up a couple Diamondine Earrings (although the price of these may change when Velious is released).

Other than that, go to the wiki and search equipment by class. You can filter through the items by stat, makes things easymode