I think you mean say or pronounce, not read. When native English speakers see the name of a place we do not know, we just guess the pronunciation from comparisons with similar sounding English words. There is an unusual English word "coper" which is pronounced in standard British English /ˈkəʊpə/ I am pretty sure that Slovenians would pronounce the first vowel more like /ɔː/ in "hot" and they would probably articulate the /r/ But you would have to ask a native Slovenian to be more sure.