What do you have in stock? I might be interested
I use something somehow similar to Ray's suggestion, see the pic below.
Those are pepper seeds and not pollinia, but the idea stays the same: small plastic bag for isolation, a sheet of protective layer, inside a folded greeting card.
When sending to the same country or EU I use a bit more padding, or a bubble mailer. To keep a low profile and avoid the package being destroyed by customs when doing it internationally, I just use simple envelopes.