Good luck with buying wine in Lombok, except at a restaurant,bar,club, hotel etc, And it will never be what would be considered a reasonable price, given the taxes on 'luxury imported items'.
Beer, of course, can be bought.
Spirits is a bit like wine.
If you are interested in local Arak ( of the safe non-lethal variety), you should contact cabehmerah! here on Lombok lovers.
But I am far from the epicurean delights of Sengiggi, so locals there might have a better perspective!