You won't find any published grand Piano MSRP, but

you can walk in authorized Yamaha dealers and work with sales reps to get their original prices. Don't pay a price they offer for your piano in the beginning. You can bargain for less, much less. The price I gave to you was out of a local Yamaha dealer in Southern California when I first talked to a sales rep in November 2008. I bought my new Yamaha C series piano more than ten years ago, and I have also helped two friends buy their Yamaha pianos at very decent prices.