yup, it's very tough to get seeds nowadays. 99% of the weed around here (NY) is seedless, so cant get bag seeds. the one weed you can find seeds in the bag with some consitency is mexican brick, which is almost always a pure Sativa. sativas are nearly impossible to grow anywhere north of essentially the mason-dixon (unless it's hybridized), the're tall, lanky, and dont yeild much, plus very very easy to spot.
if we were to do this, we'd need the support of a seed bank in amsterdam, someone big like nirvana or sensi, and we'd need a way to get tonnes of it into the U.S, and it would be have to be a charitible thing on their part because seeds are very, very expensive.
what i reccomend for a project like this, at least in the north, would be an auto-flowering strain. (ruderalis-crossed). they dont require the 18/6-12/12 switch in time period, so they start budding very early, and you could theoretically harvest bits of the plant throughout the summer, before the final harvest. some strains have a very short life-span, they can grow, flower, drop seeds, then grow again in a single summer. they are also very risistant to everything - bugs, pests, mold, drought, humidity, low light, too much light, etc. they are the hardiest of all plants. they can also spread like wildfire, and can potentially get enormous. you can even grow them in places like alaska. check out ruderalis skunk from sensi seeds.
there's also an interesting strain called the "lowryder". it's a cross between williams wonder, northern lights, and an unknown ruderalis. the #2 version also has some santa maria genes. lowryders grow to a max of 15-20 inches, and can yeild up to 2 ounces per plant, and you can have two crops a season. it's amazing, you can have it in your garden, hiding under tomato plants or among some herbs and your neighbors would never notice - who looks for weed around their ankles? the only drawback is that you cannot clone a ruderalis, but who cares? cloning leaves you with shitty deformed stunted plants, and you need chems that could potentially harm you.
to the old or misinformed, yes, pure ruderalis is ditch weed, providing nothing but a headache. it grows all over the place in the mid and north west, and cops dont bother with it cuz it's useless. but if you cross a ruderalis with a good strain, you get the best of both worlds and the worst of neither, with good conditions a ruderalis cross will produce equal quality bud to any indica, sativa, or afghani.