Ginny Weasley was told that, once Olivander was no longer operating his shop, people would get their wands from other makers:
“Talking of Diagon Alley,’ said Mr Weasley, ‘looks like Ollivander’s gone too.’
‘The wand-maker?’ said Ginny, looking startled.
‘That’s the one. Shop’s empty. No sign of a struggle. No one knows whether he left voluntarily or was kidnapped.’
‘But wands – what’ll people do for wands?’
‘They’ll make do with other makers,’ said Lupin. ‘But Ollivander was the best, and if the other side have got him it’s not so good for us.”
Harry Potter and the Half-Blood Prince, Chapter 6 (Draco's Detour)
Were there other wandmakers in Diagon Alley? Or would you have to go to another village or even another country (or by post) to get a new wand?
[yes, there is a 'second' shop in the Wizarding World park by Universal. I wouldn't consider that canon outside of a secondary source like JKR or something actually referencing that. The second shop in the park is merely one of traffic flow and economics imo - a chance to buy a wand without waiting around for the 'wand ceremony' experience]