I own QRJets
http://QRJets.com and 12th Man Ag is correct on pricing for the flight, but that would be in jet (roughly 1 hour flight time).
A single engine piston like a Cessna CE 210 could get you somewhere in the neighborhood of $3,000 with a flight time of ~ 2.5 hours from LAS to LAX.
A lot of the pricing depends on the availability of aircraft and how far they are away from their home base for your itenirary's departure and destination.
It is important to note that all one-way trips with charter brokers require payment in advance and are non-refundable.
If we are not too late and can help you, let us know. We have a form on our website for free, no comitment quotes. We do contracts on a per flight basis (no long term agreements)