Energia

The Energia is by far the best option if you want to land heavy payloads on the lunar surface. Unfortunately, the entire project has been suspended due to budget cutbacks. Facilities and rockets have been mothballed at Baikonur and Energia/Buran and won't fly for at least five years, if ever. Cost estimates are from $100-330 million to actually use it. In any case, Energia (and the smaller Energia-M variant) is not an operational launcher, although the Russians have tried to sell its services to Western customers.

On the other hand, the Energia can put about 220,000 lbm in LEO, with one launch. Using the reference mission launch budget, quite a bit of hardware and fuel could be placed in orbit with that vehicle, about twice the mass of the reference mission. There are a lot of issues attached to that launcher, but the payoff is impressive.

Reviving the Energia program would be an expensive task. However, after the initial investment, the development costs would amortize over a fairly small number of launches. This will become much more feasible after the first flight, when the Artemis Project has more liquid assets to throw around.