Tesla or Teslea?

According to some sources Nikola Tesla was an Istro-Romanian. His real name was Nicolae Teslea. His father was the Orthodox priest Milutin Teslea. The original name of the family was Draghici (a name common also in Romania) but changed with the nicname "Teslea", which in both Istro-Romanian and Romanian means bass (the carpenter's tool - in the picture). His family was one of carpenters. He was born in Lica province of Istria peninsula, which was compactly inhabited by Istro-Romanians since 15-16th centuries.