Not sure of the details of what you want but it's likely some combination of the above.
Yes, you would use meshgrid for this:
The meshgrid would generate the coordinate matrices or rather the base of your vectors. Then you would need three more matrices of equal size that would be the components.
Here is an example that draws one unit vector at (0,0,0) pointing up and to the right with unit length:
s = fzero(@(s)1-sqrt((s^2)*3),1);
Now if you wanted it for the full thing, you could use s, repmat-ed to be the size of the output from meshgrid, etc.