There are also shields around, that have HCI as well as DCI. But those do not drop anymore, so they tend to be expensive.

Shields always have 1 single point of resist when unenhanced. You can see the resists gained by enhancing here:
UO Stratics - Mining

Imo, the best shield would be a valorite shield with
Self repair 2+
15% HCI
15% DCI
FC 1