Keyless entry, spare laser-cut key only?

I have the keyless entry feature. Does anyone know where I can get a spare copy of the laser-cut key portion of the remote? I'm talking about the part of the key where you push the side button and the key slides out. I don't need a full key fob/key. If so, how much?

I'd like to use this as a spare hide-a-key or a way for me to lock my keys in the car when I hike, surf, etc. and still have access.

 

Called the dealer, they'll laser cut the key separately from the key fob but it's $140+ tax. Probably going to ask around locally with locksmiths... that seems a bit steep.