Since body stores of this vitamin are usually very large, one can live for several years on low intakes before it eventually causes problems. Your only source is the milk, which is not a rich source. This is my greatest concern. I have assumed that you eat the cabbage and carrots raw for these calculations. However, your basic premise, which is that eating adequately does not need to be expensive, is accepted.
Most people have neither the knowledge, nor the interest, to do so.
All this however supposes that one lives on essential nutrients alone. We now accept that foods, especially plant foods, contain a large number of protective factors which, while not strictly essential nutrients, are important for optimum health and avoidance of disease. Apart from the beta-carotene in the carrots, and the indoles in the cabbage, your diet is singularly lacking in these substances due to an absence of other fruit, vegetables or legumes. Your plum jam might provide a tiny amount. Hence to sustain optimum health, a more varied intake of fruit and vegetables would be considered important.