Yes I did read the applicable FAR provisions in 29 and the cost principle at FAR 31.205-41 before asking the question. The provision states that Federal, State and local taxes are allowable and a Gross Receipts Sales Tax is obviously a State tax so I would assume it is an allowable cost.
The term Gross Receipt Sales Tax is not a term normally encountered in our price breakdowns. Also in reading part 29 the question came up as to why is there only one specific clause that mentions gross receipts and why is it unique to New Mexico.
I ask the question because I do not feel 100% confident that I have made the correct interpretation.