I’ve had a bunch of people interested in the Music of PSC- It was provided by a fantastic Chiptune artist who goes by the name of Syphus- check out his artist page here
His real name is Brendan Ratliff, and his music production company is called Echolevel – Check him out on Twitter, @echolevel
The tracks included in the Eurogamer version of PSC are but a few of the many awesome tunes to be found on his album pro.tect- available on bandcamp- check it out and buy a copy!