We have a 1987 mobile home that we remodled all the walls, etc. What I'd like to know is: do mobile home parks take older mobile home? And how would I get an expert to check it out?

You contact the MH park and ask them. Many set a 10 year age limit.

Even in California. Do the laws apply the same?

Here's an example of some regulations of mobile homes in at least one area of California (below).
In researching an earlier question from Florida, I found the same type information. Mobile home facilities can even prevent the sale of homes already in the facility due to appearance or non-compliance with current health and safety regulations. You need to find the exact location of th facility you want to relocate to, and find out exactly what their requirements are. Good Luck.
http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0CCsQFjAA&url=http%3A%2F%2Fnapafairhousing.org%2Fmobilehomei nfo_assets%2FRemoval%2520of%2520Older%2520Homes%25 20Upon%2520Resale.doc&ei=x6CbUu_hB8P6oASn6YFY&usg=AFQjCNE4jQYQo0tEbVJvdFaw7N4uu5Y53w&bvm=bv.57155469,d.cGU