Buy 2 lbs.
1) Put it in smaller containers, 2 separate 1lb bags, or 4 x 0.5 lb bags. Less chance of spilling it all, getting it all wet, etc.
2) Label the bags/containers CLEARLY! Once they aren't marked, identifying most of them are going to be impossible. GLA uses finely ground ferts(last I saw) which is great as they dissolve fast, but they lack grain and texture like the agricultural stuff they are made from and thus harder to guess what they are. I see people take the stuff out of bags all the time and forget to label correct. If you put them in containers with lids, label the container AND the lid.....
3) if you find you don't need as much, you can sell it in the SnS easy peasy. Air tight, it'll last longer than you need it to, so no worries. Since shipping is a bulk of the price, silly to have to reorder in 8 months if you could have saved that 15 bucks up front.