[Why is it so hard to just find driver heads without a shaft?]

This is my first time posting a topic on here.  
I am wondering why it is so hard to just by a driver head and not have the shaft included?  I’m looking for a new Ping G425/430 Max head to replace my Ping G425 SFT that I’m currently swinging.  I have the shaft that I love and just need a new head, but do not want to buy a full set up.  
Any info on this would be greatly appreciated. Tyler

[What goes on in your head when you slice?]

Honestly a little depressed that it continues to happen.  But I tend to try and focus on my next shot once I find my ball.