If it must be essential oil, i would look for combinations of Labdanum, Cedar (Atlas!) and Sandalwood, and pump up the sweetness with Benzoin or Vanilla.
However, i get better results using aroma chemicals too in the composition.
I recommend sweet woody base aroma chemicals like Givco's Black Agar, Benzoin Essence (from Perfumersapprentice.com), Oud (Aloeswood) Blend (Firmenich) and probably even Bois Ambrene Forte. Towards the sandalwood, you could use Ebanol.
Hope this helps, happy perfuming!
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