[name_f]Evie[/name_f] is my preferred spelling, but I will always only read that as ee-vee. If you want the eh-vee pronunciation, I think your best bet would be [name_f]Evi[/name_f] or [name_f]Evy[/name_f]. I think [name_f]Evi[/name_f] looks better than [name_f]Evy[/name_f], personally.