Website has some good info: "Oaktoberfest is a true German Märzen bier, brewed with premium imported Pilsner and Vienna malts. It’s spiced with Bavarian hops from the motherland, and fermented with the famous Bavarian Augustiner Lager yeast from Munich. We utilized German Hallertauer traditions for both bittering and aroma additions, adding a rich, noble hop presence to this beer."
Haven't had it, but I can guess
50% German Pils (you can use pils extract instead)
50% German Vienna
Mash @ ~154 for 60 min
90 min boil
20 IBUs of Hallertau Tradition @ 60 min
5 IBUs of Hallertau Tradition @ 10 min
Not sure where you can get that yeast strain, it doesn't seem to be commercially available, so pick another malty German lager strain (I've had good luck with WLP833 bock). Make a starter and pitch after the beer is chilled down to your fermentation temperature.
I assume from the name that some of the beer goes through their union barrel system? If so a small amount of oak ~.25 oz would be a good addition while it lagers for a couple months.
Not saying you’ll nail it on the first brew, but it should get you close enough.
Edit: Fixed the # of the yeast