For many years, the only sushi variety I would eat was avocado, sometimes with tofu. This was mainly because of the lack of vegan options at sushi takeaways. Eventually I learnt how to roll my own sushi and became more adventurous with my sushi fillings.
To roll sushi, you will need a special bamboo mat, however these usually only cost a few dollars (the same cost as a roll of sushi from a sushi train) and are commonly available at most supermarkets. In a pinch, you could also use a clean teatowel.