Hi. I got the following info from the Coaster website. http://www.gonctd.com/coaster/coaster.html
" Brief stops are made at seven stations heading south from Oceanside. Parking is free at each station the Coaster services (except Santa Fe Depot).The address and city for each Coaster station include:
195 S. Tremont Street, Oceanside, 92054
2775 State Street , Carlsbad (Village), 92008
6511 Avenida Encinas, Carlsbad (Poinsettia), 92009
25 East "D" Street, Encinitas, 92024
105 N. Cedros Avenue, Solana Beach, 92075
11170 Sorrento Valley Road, (Sorrento Valley) San Diego, 92121
4005 Taylor Street, (Old Town Transit Center) San Diego, 92110
1050 Kettner Boulevard, (Sante Fe Depot in downtown) San Diego, 920101.The COASTER operates Monday-Saturday (no Sunday service). For information on connecting transit, personalized travel planning and disabled services, call 1-800-COASTER (1-800-262-7837)."
I hope the station at Kettner Blvd will work for you. It seems that the Oceanside Station at Tremont Street is only at most about a 1/4 of a mile walk to the main parade area near the Civic Center. This estimate is from looking up street names on Mapquest. If I am mistaken, could someone please correct me?