ummmm, while that sucks and all, Vegas will never close and its no 500 miles from So-Cal.... plus its open almost all the time. its ~350-ish miles from San Diego and ~280 from Santa Clarita.
Speedworld in Whitman AZ..... 400-ish miles from Santa Clarita, about the northernmost place in So-Cal.
Firebird in Chandler, AZ...... 425-ish miles from Santa Clarita, again, northernmost place in So-Cal.
you have options if you are making the area 500 mile radius from anywhere in So-Cal. they just arent really close to you anymore.