Well of course you could end an H at the end, but only for certain names. Others you could end with "lee" "ly", "ley", "lei", "lynn", "laide" or "line"; sometimes even an "s".
Corah, Coralee, Coraley, Coralei, Coralynn, Coralaide, Coraline
Auralee, Auroralee, Auraley, Auroraly, Auralei, Auroralei, Auralynn, Auroralyn, Auralaide, Auraline, Auroraline, Aurorus
Fionalee, Fionaly, Fionalei, Fionalynn, Fionaline, Fionus
Elenah, Elenalee, Elenalynn, Elenaline Elenis
Silvy, Silvaly, Silvalei, Silvalyn, Silvias
Anorah, Anoralee, Anoralei, Anoralyn, Anoralaide, Anoraline, Annoris
Norah, Noralee, Noralei, Noralynn, Noralaide, Noraline
Tessah, Tessalee, Tessalynn, Tessaline, or just Tess.
Or you could just look up names that are similar to them, but don't end in A.
Personally, I don't think there's anything wrong with two sisters with names ending in A; most people won't even notice it.