If 6V - get a pair of Troan T-105 or T-125, this will get you 225-240 AH total bank.
If 12V - don't know. My cup of tea are AGM. Too lazy to take care of flooded batts.
Somehow it slipped my mind that you did charge it with generator during daytime. (Not a perfect way to charge fully, see the previous post). Without 120V appliances like microwave, and with a generator, you don't need more than 200-300 AH bank.
Not solar "charger" but a 100W portable kit or a larger permanently mounted system. Looking for "chargers" at Amazon etc will fetch you funny toys ~5W, good only for battery in storage. Get 100W suitcase, those are funny in their own way but 100W is still something.