The only program that can recover or export data from .spba files is Samsung Kies, so this is the software you need to use if you want to export the contacts from the backup file and save it as vCard file. However, you may need a particular version of Kies and some later ones may not support previously used and later discontinued formats.
Convert Samsung Kies phone contacts library to vCard contacts.
We have found 2 software records in our database eligible for .spba to .vcf file format conversion.
Microsoft Windows software - convert spba to vcf on Windows
A free software for managing of latest Samsung mobile devices
Convert from spba file format
The tables with software actions are a good pointer for what a certain program does with various file types and often may give users a good hint how to perform certain file conversion, for example the above-mentioned spba to vcf. However, it is not perfect and sometimes can show results which are not really usable because of how certain programs work with files and the possible conversion is thus actually not possible at all.
Apple macOS / Mac OS X software - convert spba to vcf on OS X
Management and sync utility for Samsung mobile devices