If you are going to live large using the furnace all night and lights up late playing and entertaining.... your charge will last but 24 hours max.
How many nights will you be camped?
Do you or anyone in the group have a generator? For generator charging you may need to update your charging system. LED lights and 100 watts solar will go a long way no matter what battery you choose.
Otherwise I recommend 2x Group 27 from Costco, Sam's Club, Walmart for best value.
If you will be doing this more often consider a pair of GC2 Golf Car batteries. These a 6 volt and need to be wired in series.
Either way should be under $200