I ,also, only know "what I've read", but......what I gather is , the anthers are placed in small envelopes ( I assume those little 'waxed paper'" ones, like seeds are sometimes in), and then placed in a padded mailing envelopes ,and mailed off . I suppose to store it for "home use', you would want to refrigerate it (or possibly even freeze it
) , I think as long as it is kept dry enough to not get moldy...it should be alright. Lucy, or Dee would know much more about it...and have "practical" experience!