If you're using
Nora as a full name, I'd definitely spell it
Norah. That looks like a complete fn to me, whereas
Nora doesn't.
Lenora is beautiful. However, I think it's a real stretch to say it honours
Norma. On the other hand, I can see
Norah doing that. Personally, I'd use
Lenora on its own merits. It's just a beautiful name, and if it has this extra meaning for you, then go for it.
Some others to consider:
NerinaNorinaNorminaNoelle,
NoellaNaomiNolaNolwennNadyaNonaNova,
Novia