Electric Seat Knob - Is This Broken ?

[jd9degree]

Hi,  I have just bought my first used Lexus RX350 and I have a small problem that someone may be able to help with.  The front passenger seat is missing the knob for the power seat movement forward, backwards, up and down.  I don't know if I need to order just the knob (part number LX-8492153020B3) which is available as a separate part number, or also the switch (part number LX-8492260120) as well.  I have attached a photo of the switch protruding through the side of the seat and it looks undamaged but, I cannot compare it to the other side as I am concerned if I were to try and remove the knob on the drivers side, I might break it.  I have checked the operation of the switch and the switch is fine.

Can anyone confirm the posts are normal and not missing anything, allowing me to simply buy the knob for $60 from my Lexus dealers parts department and push it on ?  

p.s I too had the loose rear view mirror and fixed it with the help of this forum.

Thanks in advance.