No, only tetrabutylborate anion can be presented. B+ in non-polar solvent - it is something from "woodoo science"
"Dissociation energies of the gaseous mono-halides of boron, aluminium, gallium, indium and thallium" R. F. Barrow Trans. Faraday Soc., 1960,56, 952-958 DOI: 10.1039/TF9605600952
"B3+" should be "cationic B(III)" in scientific manner :-). Borenium salts review is in attached link.
I assume that sterically shielded borenium salts with large, lipophilic substituents, and with low-coordinating anions like tetrakis[3,5-bis(trifluoromethyl)phenyl]borate or terakis[3,5-bis(nonafluoro-tert-butyl)phenyl]borate can be dissolved in low-polar solvents.