This is Vitobha and his consorts Rukmini and Satyabhama. Vitobha is considered to be a minor Avatar of Vishnu and his consorts are then considered to be Sri Devi and Bhu Devi.
Vittala, Panduranga and Vitobha refer tot he same deity. The primary place of worship of Vitobha is Pandharpur where Panduranga and Rukmini are the presiding deities. See the blog on Panduranga and Rukmini for more information.
The book on The Hindu Pantheon by By Edward Moor, published 1810, has a sketch of Vitobha and his consorts, plate 76. In that book, the figure is identified as Balaji.
The book on Sculpture at Vijayanagara Iconography and Style by Anna Dallapiccola and Anila Verghese has a picture of Vitobha with his consorts. Picture 55. In that Vithobha is holding the conch shell on his left hand and the consorts are depicted the usual way Sri and Bhu Devi are depicted. Holding a lotus bud each, unlike in this example where the consorts have their hands near their hips while holding two lotus buds each.
All three deities are standing in Samabhanga, without any bend. Rather unusual for the goddesses to stand in Samabhanga.
The bronzes are produced using Ganga Jamuna (GJ) technique, where lighted coloured metal is laid over copper. This technique is not widely practised now. Most of the GJ bronzes you see are from North Karnataka region and they are generally dated to the eighteenth century.
Vitobha is about 12.5 cm in height. Rukmini and Satyabhama are about 10 cm in height.