Countif with a range an criteria declared in a let statement,

Hi, is it possible to get countif to work with ranges declaed in a let statement,

COUNTIF(K3#,D3:D10)

K3 = spill from filter,

But what I have tried to do is put this into a let statement and then use it

=LET(itemList,D3:D10,n, F3:F15,it,G3:G15,fil,UNIQUE( FILTER(it,n = H3)), COUNTIF( fil,itemList))

but this results in an error? I have managed to use match,

So my question is, is there a way to get countif to work with the ranges and filter spill named in a let statement?
If it can't be done at least I can stop trying.

Richard