Welcome to the forums. The serial number indicates that the bicycle was manufactured by Kawamura of Japan for West Coast Cycle Supply, the California based importer and distributor. The date is circa 1974. It could be a 1974 or 1975 model.

The presence of stamped dropouts, top tube cable stops and flat stay caps suggests an entry level model with a hi-tensile frame. The presence of stem mounted shift levers and brake safety levers also supports this level. This suggests either one of the Sport variants or an Olympic. The lower fork legs appear to be silver paint, as does the fork crown, part of the bottom bracket shell and possibly even portions of the headset. The questions is whether the fork blades were painted to cover rusting of actual chrome or whether they were just painted to simulate chrome. This would help differentiate an Olympic from one of the Sports variants.

The wheels have aluminum rims but they are mismatched suggesting at least one is a replacement. The pedals are definite replacements. The headset has a hanger for an era and level appropriate centre-pull brake, suggesting that the brake calipers have been replaced. I can't comment on the crankset and derailleurs due to the non-drive side photo.

It's definitely a mid-1970s entry level that has been significantly modified, complicating identification of the exact model.