For reference, here are two questions that deal with wizarding population: What is the total wizarding population during the events of the Harry Potter series and How many people worked for the Ministry of Magic?

The British Wizarding population seems rather small. Apparently the entire student body of Hogwarts is able to fit into the Hogwarts Express (According to Pottermore -- [1]3, [2]4 -- the Hogwarts Express is the only way to Hogwarts; it's not like some students ride the train and some students are dropped off by their parents for the school term.).

How many wands would Ollivander have to keep on hand at any given time? We know Harry tried out a lot of wands before his wand finally chose him. Maybe some kids need five tries; maybe some get the right wand on the first try. And there are broken and lost wands that need replacing to take into consideration.

I don't consider the movies canon, but as they're JKR approved, Harry Potter and the Sorcerer's Stone shows Ollivander has a pretty significant number of wands in stock for what is a smaller Wizarding population (see pics). Is there a canonical way to estimate how many wands Ollivander would need to keep in stock?

I'm looking for an answer grounded in canon, meaning the novels, interviews with J.K. Rowling, or information from Pottermore or the like. Barring that, a speculative answer in the spirit of canon is absolutely welcome, including alternative sources of information. ETA 12.21.14