Can also check out soshigoods.com they are cheaper than yesasia, but don't do free shipping so could work out about the same costs. You can search by artist and see what they have for each artist. Calenders are tricky in Kpop. Generally they are like part of a pack or not official or something. Kpop artists who release in Japan tend to do calenders, but SM are releasing some for their artists this year, sadly not SUJU, just SHINee of the male groups...
What dudes does she want? I can look around/ask around.