This is something the electrician would normally do - I presume you are checking on what he charged you ? You should have the original inspector signed-off permit left in the house for proof the work was permitted, probably has cost written on it. Depends on your area - some areas start as low as about $25-50 for a permit, others more like $150-300, some minimum $100 or so but additional based on $ amount of the work. Normally the fees are on the building department website. Usually, except for large cities using permits as a way to raise money, around $75-125 would probably be fairly common for this type job. Of course, electrician would charge you more, especially if he had to physically (as opposed to on web) go get the permit himself - that could add $50-100 real quick for travel time.