i have a 04 SE.

let me set the record straight from these guys,,,

i have 18" wheels and i off road my rig all winter and summer. i DO NOT rock crawl and do not want to. for all the off roading i do local i have never had any issues on my 18" wheels.

there are too many other things that can be a deal breaker that top the list over what size wheels are on the rig. you can buy a set of 16" wheels for under $500 after the purchase.

just make sure everything works. all the electronics. make sure it has a service history on paper.

if there are any issues and they are small and easy to repair thats not bad. if it seems like a bad deal then walk away. if it feels good, then go for it.

 

If you are in California, you will want to trade wheels for a set if 16's, don't run 2 different tire sets, there are plenty of dual purpose 16" tires that will work well.
As for clubs, if in the LA area, Southern California Land Rover or in San Diego, the Land Rover Club of San Diego.