I can get some agar from a plant science friend, and was considering filling a large jar with it, then sterilising it all with heat. Then, mixing the seeds with hydrogen peroxide and sowing the seed-h2O2 mixing the agar. Either he will have a glove box, or i use a heat vacuum to block pathogens going into the jar when I open it
Some folks put a rigid mesh on top of a large pot of boiling water, then do the flasking by working on a plate in the middle. The rising steam supposedly keeps pathogens away, by thermal "sweeping", if nothing else.
Thats pretty much exactly what I meant. That seems like a great way to do it.
So far, I'm thinking of putting the agar in the jar and shallow boiling/steaming the jar with the lid open. Once I've got it hot and sterilised I'll seal it up and wait for it to cool enough so that the heat doesn't destroy the seeds. The trouble of opening the jar to put the seeds in is the trouble of contamonation and perhaps using a mesh to put the jar on for that sweeping hot rising air may be the way I actually get the seeds in the jar safely.