You won't be able to get those drugs without a prescription, so, that idea is off the table.
Why would you want to anyway? Do you actually have all that much stuff to do you need to sacrifice sleep? If you do you really need to reassess that, if you don't actually need to do all that workload you need to look at how you think. If you have an attitude you need to work constantly, to the point of willingly giving up sleep on a regular basis, that isn't a healthy attitude. Might want to take a peak at the idea of a work/life balance.
These drugs are often used by people who actually need them, narcoleptics and the like. Other times they're used by the military and other civil forces but they actually have a legitimate reason to do that. They don't do it on a constant basis either.
We have to be cautious of extending a specific case to the general. Its (supposedly) true that man didn't sleep for 38 years without any ill effects but what about the other billions of people that don't and can't do that. He might of had some kind of neurological or endocrine condition. Not exactly something to wish for.
I'd imagine there aren't many if any studies on long term sleep deprivation (that's what you're suggesting to do to yourself afterall). People who sleep less than 7 hours a week tend to get more sick and live shorter lifes than those who sleep 7. This is also true for those who sleep more than 8 (supposedly). As far as i remember reading anyway.
Sleep deprivation is really not something you want to do, at all. It messes with your immune system, your brain, your hormones, your skin/complexion, ect.
Also if none of this is true, i think sleep is important just psychologically, to break days apart. Imagine if one day constantly ran into the next one and they all blurred together, i would think it would be quiet horrible. Your mind needs a break really..
Also i remember shift work induced sleep disturbance being listed as a confirmed carcinogen (causes cancer) or a highly suspected carcinogen.
It might seem like a good idea but think about it, if you miss out on sleep to that degree you will (most likely) be tired for most of the day. I remember i did this during a lot of highschool (not that i was working during that time, was just talking to friends and such) and the next day i was absolutely dead tired almost falling asleep in class and when i got home on the desk. Sure, you might gain a couple hours a day by not sleeping as much but its definitely not worth it if you spend the rest of the next day absolutely dead tired and not able to work at efficient levels.
Also sleep is bloody awesome...just sayin'