But again, it comes down to what people are prepared to pay for the real thing. Now TBH, I enjoy the scent of real sandalwood, but I don't personally want a soap made with it. Others will differ, as they should. But you already have a premium product (and I mean that), so having an elite line of authentic scents won't hurt, people will still jump into line to buy them. You could always make it a limited edition if you're worried about being stranded with excess stock.
If your definition of a prohibitive price is $35 per tub, consider the price of a tub of A&E, NO or most of the others. Yours will stand up in a comparison of value for money.