Transformation through realization a.k.a enlightenment is a recurring theme in eastern philosophy. Is there a counterpart for this in Western Philosophical writings?
"Transformation of self" and "transformation through realization" are both pretty opaque statements. There's definitely themes of "transformation" (e.g. Plato), "enlightenment" (e.g. Kant), "progress" (Hegel, Marx), "authenticity" (Kierkegaard, Heidegger), wonder (e.g., Plato, Aristotle, Aquinas), and other things through the philosophical corpus.
If your specific question is about the self, then there's a lot on the evolution of the idea of the self in Hegel's Phenomenology, Sartre's Being and Nothingness, Anti-Climacus's [Kierkegaard's] Sickness unto Death and Taylor's Sources of the Self.
If you mean specifically the religious-spiritual mode in which that occurs in some eastern thought, there are similar traditions about self-knowledge before God in the Christian mystics and some Western philosophers.
Like many philosophical concepts, one need look no further than Plato. The Delphic maxim γνῶθι σεαυτόν or "know thyself" is oft used by his protagonist, Socrates.
The phrase you are looking for is the "beatific vision". It is the idea that our perceptions of beauty, truth and goodness in this world are a glimpse into a deeper reality which is accessed through the soul and self knowledge.
The first occurrence I know of is in Plato's Republic, which explains how seeing the Forms frees a person from slavery and teaches them who they really are, and uses the city as an image of the soul in order to understand a correctly ordered soul.
This theme is picked up by Christian philosopher theologians such as Boethius, Augustine, Justin Martyr, Bonaventure and Aquinas. It is also a standard hermeneutic principle during the Middle Ages, where the deepest meaning of religious scripture is how the soul achieves the beatific vision. In fact, it is the defining pursuit of philosophy and theology during this time.
The best popular expression of this idea is the Divine Comedy by Dante, which is a story about the escape of the soul from a false understanding of self to achieving the beatific vision.