Raymonde is pronounced [reh-MOND], so the "
Ray" nickname isn't intuitive and I guess most people would butcher the name as "
Raymond" anyway.
For '
Ray' I'd go with something like
Rachel,
Rain,
Reina, or the Japanese
Rei (or Reika / Reiko) (pronounced the same).
More ideas (even if some are a stretch):
Mireia /
MireilleLorraineIgraineAndreia [un-DRAY-a]