Hi,
we're a small software house form Poland.
And we're quite suiteable for the task, we do use Django a lot.
We don't use mercurial, we used to use SVN and switched to GIT like the mainstream.
Beside that we've got experience in python, django, html, Javascript, CSS, jQuery, Angular, Postgres, Bootstrap we use quite the same technology stack as you do.
Please don't hestitate to contact me if you have any further questions.
best regards
Kacper Świętkowski