Della, I freeze pollen all the time---well, almost. It's necessary when you want to cross a late bloomer to an early one, which happens quite a bit around here. I save pollen for about 4 or 5 years then generally replace with new or something else as need be. I have used 4 year old pollen successfully and I suspect it might last longer, even. My freezer is NOT a frost free type and that might have a positive bearing, however. Using normal pollen preparation for drying, I store it in 12 ml glass test tubes topped with cotton in a common test tube rack and then kept frozen a around 0'F. When I select a pollen to be used, I remove a couple anthers and allow them to come to room temperature for an hour or so. I always work quickly when retrieving the test tube and placing it back in the freezer as moisture will condense very fast both inside and outside the tube--in other words, I never take a tube of pollen out to the garden and then return it to the freezer. That way the remaining pollen stays frozen as well. I have a couple pictures I'll edit in later.
Pollen can be shipped from one continent to another and from one hemisphere to another, almost anywhere successfully. About a fifteen day shipping time seems to be no problem as long as the samples are properly dried. The most common time to ship is right after harvest.
Photo added
