Seems kinda dead in here . . .
Does anyone know where the original PoR can be obtained?

Hmm, if you ever see Wingfoot in the chatroom, you can ask him directly as he has it. But I believe he said he got the game in some D&D silver collection. Unfortunately, I don't remember more about the actual name of the collection. But I know he got it in a collection of games that had silver in the title somewhere. I'd also try asking around in the whatnots section. Just don't mention anything about the sequal or Sorcerer will send your post back here :)

Go here:
http://www.sorcerers.net/Games/index.htm

and scroll down a bit to find the Forgotten Realms Archives Silver Edition. $20 and contains 14 games including Pool of Radiance.