Iona, Ysella (ee-sella), Lois, Ines, Estella, Oona, Cassia, Serena, Fenella, Christa, Christabel, Elowen - all fairly unusual
Stella, Clara, Zara, Sara, Lara, Annabel, Eloise - not unusual but no where near as popular as Isla, Iris, Isabel/la, Eleanor, Emilia, Mia etc (although there are a lot of short L names overall - Lola, Lily, Lila, Lyra etc so I would maybe avoid Lara for that reason, and maybe also Elowen and Eloise because she’d probably end up another Ellie)