During the study for Economic valuation of forest ecosystem. I found that the community depended on forest ecosystem services are used the various types of material and foods for their needs despite of sale it in the market. So I got the Market price from the Forest and Govt Agriculture site of that product. But I didn't found any references about the hypothetical price taken before any research papers but I strongly believe that I can take the hypothetical price of ecosystem products especially for the replacement cost method.

So, if anyone can refer me such research papers or a justification. It would help me for my research paper.