Answer
(Fatwa: 790/622/B=1431)
Since the cross is amongst the symbols of Christians and its business tantamounts to promote the Christian symbol; therefore it is makrooh. Almighty Allah says in the holy Quran:
وَلاَ تَعَاوَنُواْ عَلَى الإِثْمِ وَالْعُدْوَانِ وَاتَّقُواْ اللّهَ إِنَّ اللّهَ شَدِيدُ الْعِقَابِ [المائدة : 2]
And do not help each other in sin and aggression. Fear Allah, surely Allah is severe at punishment.
و فى الدرالمختار و قيل يكره لإعانته على المعصية (درمختار 9/561 حظر والإباحة فصل فى البيع ).
Allah (Subhana Wa Ta’ala) knows Best
Darul Ifta,
Darul Uloom Deoband