ExpertFlyer shows prices for all fare basis codes.
It's hard to understand the issue. You have already found a way and just want a faster way? Or you literally cannot see the more expensive fares which would be the ones WS wants to sell you. Flex Y or whatever they call it. I can't imagine on WS website the higher revenue fares are not front and centre. Though I use a TA and fly Flex Plus or I guess the new J if they offer it. The TA has all the fares too.