existing or done for a good reason, and therefore acceptable synonym legitimate justifiable pride
NAmE//ˌdʒʌstəˈfaɪəbli//, NAmE//ˈdʒʌstəˌfaɪəbli//
adverb The university can be justifiably proud of its record.See justifiable in the Oxford Advanced Learner's DictionaryCheck pronunciation: justifiable