Does supplication by means of a sincere righteous deed fulfill its doer's reward in this world, thus depriving him of recompense in the Hereafter? And is it permissible to repeat the supplication using the same deed more than once?

Interceding with Allah Almighty through righteous deeds is desirable, and it is a cause for the acceptance of prayers. The reward for this deed is not diminished, whether the intercession is for the attainment of a worldly or an otherworldly matter. Furthermore, there is no harm in interceding with a single righteous deed more than once.