Ruprecht is ideally located near Bern main station, but has normal limited opening hours, so if you happen to be in town after 6.30pm, visit the Reformhaus Ruprecht in Loeb Lebensmittel instead, which is just round the corner.
They have a good selection of vegan cheese, faux meat, soya yoghurt and various vegan milks (soya, rice, nut and grain milks). Ruprecht is an organic shop and also offer a wide range of organic oils, vinegar, grains, pulses and natural sweeteners. They also have a list where you can check which of their wines are vegan. If you're looking for a particular product you can't find, just ask the staff, they'll order it especially for you. I have done so quite a few times and it worked perfectly.