SEAL, O-Ring (Intake Manifold) Included in Carburetor Kit-Part No. 493762. Included in Carburetor Gasket Set-Part No. 490937
JET, Main OR 494870 Screw-Bowl Mtg. (High Altitude) Part number has dual meaning - in some cases it's a std jet; in others it's a high alt jet. See hard copy (paper or fiche) of appropriate parts list to verfy part usage.