I am attempting to see the prices for tickets from Chamonix-Mont-Blanc to Interlaken West. The passage will be Chamonix-Mont-Blanc to Vallorcine to Martigny to Visp to Spiez to Interlaken West.
I am able to see the prices for the section of the trip from Martigny to Interlaken West.
I get this error message for Chamonix-Mont-Blanc to Vallorcine, Chamonix-Mont-Blanc to Martigny, and Chamonix-Mont-Blanc to Interlaken West:

Why can I not view the price? Am I just unable to book this section through SBB or am I unable to book it online? Regardless, where can I find pricing for this journey?
If I want to buy this trip using a Eurail pass, should I call in the purchase?