P/E ratio equals share price divided by earnings per share. The share price of unlisted enterprises can only be calculated at its transfer price, that is, the actual transaction price of non-public transfer. Usually, the actual transaction price will not be too far from the net assets per share.
In your situation here, you must first have a company's valuation or the other party's bid for you. Dividing this value by your total share capital is equivalent to calculating the price per share, and the earnings per share are ready-made, so you can estimate your P/E ratio. Hope to adopt.