I already had installed libglib2.0-dev package, but the installed version was too new for libpulse-dev.
The solution was to install libpulse-dev using aptitude. Aptitude did automatically downgrade libglib2.0-dev to the required version.
ftp.harukasan.org is selected by the Raspbian mirror redirector (raspbian.raspberrypi.org, which is not a "real" mirror server).
To speed up, you can specify the nearest mirror server in /etc/apt/sources.list, by replacing the raspbian.raspberrypi.org to the nearest server's "real" address.
The nearest server could be found here:
You have provided no evidence of any problem.
I know of no way of blocking a mirror, but you can change the mirror used.
Select a mirror from https://www.raspbian.org/RaspbianMirrors/
Then edit /etc/apt/sources.list substituting a local mirror for http://raspbian.raspberrypi.org/raspbian/
A more verbose set of instructions are in https://pimylifeup.com/...