yours looks like the ones at the bottom, so yeah you've got yourself a 100usd game right there, nice dude
Let me detail the situation.
Firstly, PS2 versions of the game are outright worthless. Don't bother.
Jewel-Case and Reprinted/Republished versions of the game don't include the manual or box and are not worth above $150. This is because the game was never released as Jewel-Case only, meaning that the seller is giving you a used, incomplete copy and the republished versions are just stuffhouse.
The boxed set, opened or not, is worth a minimum of $250USD. Copies on Amazon go for $300 or more.
I owned the game and my disc has gone missing. I still have the Jewel-Case. The game is good because the engine is one of the most flexible I've ever seen; EXTREMELY moddable.