I've never heard it before. I like it better than Pearl. But I think I would just assume it was a nickname for Pearl. I've googled it and see it's just a less common, vintage name with the same roots as Pearl. It's prettier, I think. Go for it if you like it.
Other ideas:
Agnes, Angel, Anna, Annie, Alice, Alma, Alba, Avis, April, Avril, Ada, Ava, Aphra, Bonnie, Belle, Bella, Betty, Beryl, Blythe, Cora, Cara, Clara, Carla, Connie, Celia, Calla, Dana, Dora, Daisy, Etta, Elsa, Ella, Eva, Esme, Effie, Elsie, Elise, Edie, Edith, Enid, Eve, Erica, Faith, Fleur, Faye, Flora, Fabia, Grace, Greta, Gloria, Heidi, Honor, Ivy, Iris, Isla, Inez, Ida, Irena, June, Joy, Joyce, Judy, July, Jean, Kitty, Kate, Lily, Lucy, Lydia, Lara, Mabel, Maeve, Maggie, Martha, Mary, Maisie, Nancy, Nell, Nelly, Nora, Opal, Orla, Olive, Polly, Peggy, Posy, Penny, Pippi, Pippa, Rose, Rosa, Ruby, Rita, Ruth, Sarah, Sally, Sadie, Susie, Sylvie, Sylvia, Tilly, Thea, Tessa, Tessie, Tara, Una, Vera, Veda, Vita, Willa, Winnie, Yvette, Zelda