Formula to generate Dynamic Unique List from another worksheet

[SoleAris]

Hey all,

I need to generate a unique list of values for a table I'm creating based on another worksheet's table. This seems so straightforward, yet for some reason it's giving me some trouble.

Attached is an example workbook, where "Order Details" is the table that I am looking to base the list off of (the Carton # column) and generate a dynamic unique list in the "Carton Info" worksheet, which will list those unique values in the Carton # column.

Here's what I've tried thus far:

COUNTIF to get a value of 1 for the first unique carton # in my table and a value of 0 for all repeated values:

=(COUNTIF('Order Details'!A$8:A8, 'Order Details'!A8)=1)*1

From there, I can count my number of unique values through a SUM function. From here, I tried the following and can only generate the first value before getting "#NUM!" errors:

=IF(ROWS(K$8:K8)<=$J$8, INDEX('Order Details'!$A$8:$A$27, SMALL(IF('Carton Info'!$H$8:$H$27=1, ROW('Carton Info'!$H$8:$H$27)-ROW('Carton Info'!$H$8)+1), ROWS(K$8:K8))), "")

I know my error comes in the bolded section of my formula, but I cannot figure out how to fix it at this point (been looking at it for too long). I'm sure there is a simple way to have Excel simply count up from 1 to a certain number in increments of 1 until it gives me the value of the SUM function (of unique values), however I would also like to see if there is a cleaner formula out there to do this.

Thanks for the push!