If you download the image below, you could add it as a custom colour picker.

This only really works if the colour picker is set to HS/L mode.

To do this, click on the current colour at the bottom right of the picker and choose HS/L Picker from the list.

Now add the custom colour picker like this:

Click the current colour at the bottom right of the picker and choose 'Custom Colour Pickers'

The custom colour picker panel will open.

Choose a group to add the new picker on the left ( I just chose 'Pickers )

Click the 'Import Picker' button then browse to the image file you downloaded ( Cellular Picker.png ), select it and choose 'Open'

You should then see it added to the current custom picker group.

Click it and close the panel.

This was made using a similar method to the one Roma Golich described.
I took a screenshot of the colour picker, pasted it into Irfanview, cropped it then reduced the colour depth

I hope this is of some help!

EDIT: Replaced image with a better version

Name:  Cellular Picker.png
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