Ginkgo Biloba, It is fairly cheap and you can buy it at pretty much any store - supplement section.
Melatonin, same thing as G.b it is fairly cheap and found at pretty much any store - supplement section.
Fish oil, Not only good for lucid dreaming but very good for the brain. It depends upon the person when the lucid dreams start to happen, could take a week or days.
Also congratz on quitting/stopping weed