Complex sentence: From the beginning the Musics collective took the principled position that they would not accept paid advertising or grant aid and the only income came from subscriptions and sales through (mostly alternative) bookshops and associates in cities such as Bristol and Glasgow who sold copies at performances.
Split into simpler sentences: From the beginning the Musics collective took the principled position that they would not accept paid advertising or grant aid and the only income came from subscriptions and sales through (mostly alternative) bookshops. In addition there were associates in cities such as Bristol and Glasgow who sold copies through local outlets and at performances.