The Specialized Roubaix (among many others) was only available during the mission it was used for. It pains me that my actual bike is modeled in the game but I have no way of actually using it!
That would be up to the bike manufacturer, I’m sure Zwift would love to put a lot more bike sales into the game.
Also, name a easier way to add more levels as people request. The diamondback wheels could be 26, roubaix frame 27, etc…