Congrats on your purchase. Hey, nice color too.
You can start your search with this link:
You can also take a look at my buddys web site and take a look, but you've already made your purchase. Still it's fun to upgrade but everybodys needs vary.
I strongly suggest solar for the purpose of maintaining good battery health. You really don't need a huge panel but more will recharge faster in the field plus if the sun is limited, more panels help. Hopefully the previous owners did a solar prewire.
Lots to read on the site...good luck.