Hey, well I know this thread is from last year, but I read it while I was searching for the exact same thing (Mescaline extraction anyone?
) anyway I thought I'd sign up and just share this site with you
I've never ordered from them myself, but it looks legit, and there's a review on the 25gram one which says it's good, so I reckon it'll be fine.. I also emailed the site admin asking if they shipped to the UK and he gave a very friendly response so yeah, sounds legit to me, quite cheap, though sadly not a KG, only 250 grams for $150, (Plus $20 postage to anywhere outside of the US), but I worked out it's about £105 if anyone's from the UK here so yeah, have a site link
http://psychoactiveherbs.com/catalog/index.php?cPath=133_122
Also has some other cool ethnobotanicals by the looks of it..