Ignition switch or Lock assembly?

Bruce responded to my earlier question and I now have a second part to it. I have a 1998 honda accord ex, 4 cylinder, 5 speed manual. About 160,000 miles. The key will not turn in the ignition. The steering wheel is not locked and I tried a spare key to check the keys. The spare would not turn either. Bruce recommended replacing the ignition switch. I called a honda dealer and told them the situation. They told me I had to replace the ignition lock assembly. They said they could replace it and rekey it so I would not need a new key. I was told the ignition lock assembly part would cost me $213.00 and labor would come to $315.00. $528.00 seems like a lot of money. I found the lock assembly online for $177.00. The switch is only like $30.00 someodd dollars. Before I spend all this money, how can I tell whether it's the switch that needs replacing or the whole lock assembly?