I happen to have these parts laying around so if you want you can take a look. The green circular part is the Seal Ring that is used between the EGR mount pipe and the crossover pipe, and the rectangular gasket with the red sealant is the Intake Gasket used between the crossover pipe and the intake manifold. The prices are for my local dealership. The intake manifold gasket itself is around $10 - 12 here from Fastlane, I think.

I just started taking this system of my 603 and there is a 3-5 mm of "tar" coating inside the crossover and it looks like slightly less throughout the intake manifold. The closer to the EGR the more cooked it appears. If anyone has any useful tips on what solvent can be used to remove these deposits please don't be shy!