Need help/advice on how to do so given my current gear and how much that will cost.
He Sequitur, as promised here is the advise for the upgrade route (sorry for the delay been busy). You mainly need life > armor > dps > resistance. In that order. Hope this helps.
1. Replace mempo, find something with high dex counterpart with vit or something with cc (could be pricey, and personally i wont go with mempo not unless cc). Or replace it with an inna's helm you still lack some armor so you can go with dex/vit/allres/armor/cc inna or dex/150+vit/allres/cc counterpart.
2. You can go with double vit rolls for pants and shoulders (vile wards). That should cover for replacing the ice climbers with a nats set.
3. Nat's boots with vit and maybe replace the unity ring with a nats ring with ave.damage/aspd/cc. (ring replacement i would leave up to you, both rings are nice).
4. Off hand weapon. Get something with at least 1000dps/100dex/50%cd/2.9-3%LS (if you go single LS for higher mp's you need the most you can get).
5. Lastly is stat perfection: Ammy can get higher cc and cd. Gloves with aspd. Bracer with higher vit. Belt with dex. And lastly chest armor with 3 slots (but I guess this will be the last one I'd replace).