Just take the easy way out and buy a semi-auto reproduction for a $1,000 or so
http://www.auto-ordnance.com/Firearms/Thompson-T1.asp

>rich people
>repros

If I were to ever buy one gun, it would be the M1A1 Thompson. Why? Because WW2 guns are the best. And it's my favorite gun of all time. One exactly like the picture, not one with the pin on top.

I'm at dinner but this came to mind.

How hard is it to find an original, non replica? How expensive do they go for? Also, I know literally nothing about gun laws and such, and I can only assume I'm to young to own one legally, but when would I be able to get one (not saying I will). At 18? I live in Florida.

You want one exactly like the one in the picture?

Alrighty the entire process will take about 9 months because you need a a Class III permit to buy a SBR. Then the government has to do a thourough background check on you, then you have to find the right dealer. A fully automatic SBR will cost you anywhere from $20,000 to $50,000+, and if you want an original you should expect the price to be even higher.