Four essays by Alistair McConnachie, who was frozen out the UK Independence Party for his opinions, are on sale in the politics section.
The essays, which refer to "stupid Scottish separatists" and "socialist domination for all eternity" under independence, fill one-third of a book called A Force For Good. The Parliament last night said it not received any complaints but would "reflect on whether it is appropriate to continue stocking this title".
In May, the Sunday Herald revealed McConnachie had become an official campaigner for a No vote by registering with the Electoral Commission as a "permitted participant".
Ukip's Scottish organiser from 1999 to 2001 and a Ukip candidate five times, he was barred in 2001 because of comments about the Holocaust.
In an email to party members, he said: "I don't accept that gas chambers were used to execute Jews for the simple fact there is no direct physical evidence to show that such gas chambers ever existed ... There are no photographs or films of execution gas chambers ... Alleged eyewitness accounts are revealed as false or highly exaggerated." Ukip refused to renew his party membership.
In 2007, McConnachie wrote he was not a Holocaust denier and was "quite prepared to accept that six million Jews perished in the Holocaust", but added: "I've questioned the existence of execution gas chambers."
SNP MSP Stewart Maxwell said: "Mr McConnachie's publicly expressed views are sickening and it is disappointing that the No campaign have not publicly condemned his status as a permitted participant."
Better Together has previously denied any knowledge of McConnachie.