One last question: How would one talk to Palax? Would I have to go through an intermediary or does she hold court?
I'm finishing my backstory, and I need to explain how I came by the scales of a metallic dragon, which are essential ingredients for the Ritual of Rebirth.
Fairly easily. Silver dragons are like Gold dragons in that they often take mortal form and hang out with mortals, but unlike them in that they tend to avoid combat rather than going crusading constantly. Palax is a regular visitor for the Magistry and a semi-regular one for the city and villages. Her lair is in a cave at the top of the waterfall which drains into the lake, so visiting in the lair is basically a matter of "Has permission and is brought up by Palax," "Has permission and can fly themselves," "Has permission and absurd freeclimbing skills," or "Does not have permission and enjoys extreme high-diving."
Basically if you were at the Magistry at all, there's a decent chance of meeting Palax at some point or other. The source that I'm using as a basis for more complex behavioral patterns suggests that Silvers tend to spend a substantial amount of time in mortal form, sometimes living out entire mortal lifetimes while rarely going big-and-scaly. So for things related to anything except certain trouble issues, about as close to Mister Rogers as you're going to get from a dragon. It's entirely possible that being a cleric of Bahamut seeking to become a Dragonborn would be sufficient when coupled with a humble request.
You could also have found them in the shallows of the lake or something. :V