I got a iSCSI target to work on my redhat with a USB disk to test iSCSI storage pool and found below:

1. When create a iSCSI storage pool, I selected a target in dropdown list.
2. Once the pool is created, I see a volume named 'unit:0:0:1'.
3. When edit template, in the 'storage pool' dropdown, 'unit:0:0:1' is listed there.

So 'unit:0:0:1' which indeed is a volume but listed as a pool in template?  or something I am misunderstanding?