I have a JTech Photonics 2.8W Diode Laser for sale. This laser is amazing, I just upgraded to the 7W so do not need it anymore. All original cables, etc included. $200
Regardless of how much time is on that diode the price is a steal!
The power supply alone is well worth it too.
I was using this with my Shapeoko 3 and I put a few hours on it, but I did not have a production shop or anything so just hobbyist hours. I do not have any way of giving an actual number of hours though.