We do have and keep backups from back then. (Well, close to, at least.)
I'm not in a position to release worlds though.
However, warps and stuff like that from back then will not work. So travelling to places will require either manually walking to said place or /tp'ing there.
Also, you'll have go into peaceful mode in order to keep mobs from spawning pretty much everywhere.
edit: I (or you, depending on what I can release) will have to convert from the old "single .dat per chunk" format to the Anvil system that is used nowadays as well.
The closest backup I have found (and am able to convert) is 2010-11-12_1100.
Unless you run a server yourself and block all block updates you'll have a hard time trying to run this map because of all the old leaves blocks everywhere and other such "features" that notch fixed overtime.