Create userform with dependent combobox based on different tables

I want to have a userform where combobox2 "Description" is based on combobox1 "Funding". And combobox3 "Item" is based on combobox2 all in the SAME table (T_FUNDING).
This I have help previously to achieve with thanks to members here!

What I want do now is keep the above relationship between the comboboxes, but add an new relationship:
If "stock" is selected in combobox2, then I want combobox3 NOT to refer to T_FUNDING table, but refer to column 1 in T_Stock table. And the related code to be column 2 in T_Stock.

How do I do this?

Good idea @torachan! I played with it and the userform and the table will functionally work doing this.
However, this causes a problem with billing as "Stock" will replace the place where the Funding (or billing body) is. This means afterwards I will have to manually replace "stock" with the correct billing body. Any way around this?

I think that could work too. I got around it by doing something that I don't think you will approve of?... I combined vba and formula. I used the userform as you suggested and added formula in the data table to pick up the funding body without the userform.