Pills
Need a quick stat boost? A little edge to solo that cash? Pills may be your answer. You want drugs. Blue ones, red ones, stims, poppers, tablets, capsules, caplets, caps, lozenge, pastille, all the varieties you could ever want. Each pill boosts a stat; ask for them by their generic names, str, wis, etc...
Pills weigh almost nothing, last a long time, and can be stored in handy pill containers purchasable at the Alchemist guild. Pills are manufactured by alchemists using the mix drug skill. Not all alchemists hold to drug manufacturing however so seek out the shady ones in the backstreets of Esiris. Stronger varieties can be manufactured by those with a high knowledge of pharmacodynamics skill.
A word of warning though, as with their real world analogues you might becomes dependent. But perhaps death cures that and you die all the time, right? If not a reinc surely will.