good luck - why do you need a holster on a car seat? do you realize how bad that has the potential to be? unless you are meaning to put your gun while driving - aka for the driver seat?
I cannot carry at work but I can carry to and from work. I need the hiding place for when I am at work. I think that under the seat or perhaps an attachment to the door trim panel may be the way to go. Secure, accessible, outta sight.