I can only afford one pound of prime rib. Can it still be cooked to medium rare?

Perhaps it'd be better instead of roasting in the over to sear it in cast iron first on both sides, then put it in the oven until it reaches medium rare temp. Saute some mushrooms in butter and deglaze in red wine and herbs. Then pour on top. No matter what, use a digital meat thermometer to get it to the correct temperature, and make sure you let it rest.