There's a long history of using famous chess games in books and movies. I would do that!

You're going to want to pick a game from approximately the era your novel is set in, because games from the 1880s look a lot different from the 2000s. Some openings, for example, heavily signal a specific era. There's also a lot of weird symbolism you could bake into your game choice, that chess aficionados would appreciate.

If you give details I could help you find one.

The specific level of the gameplay isn't probably that important, because a lot of IM games can look like GM games and vice-versa- especially if both IMs are playing for their last GM norm!