You have a few choices but nothing great because there all Hobby People . The easiet one close to LAX is off of Hawthron BLVD aprox 15 min from LAX .
Now if you go to the corporate HQ , its about 40 mins , again an easy ride same direction
Once your at Hobby People, main office , there is a one good independant shop off forest drive , again traveling a little more west once getting back on the highway .

On RC groups -under warbirds there is a member by the name kentucky Kernal , he lives in the area can give you the exact name of the independant shop
With all the great rc enthuist in southern cal , I have always been disappointed with the rc shops in SCal . hobby people controls the market and most have aprox 2 lanes for planes and then its all cars