Hi. I am a passionate classic player and wish you well. i have never done a SP build but i play HCCL most ladders
For basic easy to acquire from nm items to beat hell i would aim for:
Shard, full irthas set, 3 socket tower (so u have mb with holy sheild) with 3 perf diamonds (if you cant stand silver sheilds then use ruby/saph/topas first for desired colour / res needed and 2 perf diamonds. Amulet rings are they pretty free for options as you already hit 50fcr breakpoint. however if u find 2 fcr rings and amulet u can hit the 75fcr bp. I always avoid MF items on hell cos i don't want sets and unique after I have obtained the items i mentioned previous.
From there you should look for high def items with life res and FHR but first two most important.
On my ladder classic pala this is the way i start out and endgame is a 50 fc build with a pala septer, magefists, Fcr rings and fcr amulet - with mage plate, grim helm and shields
Wish u luck on your walk