I allow 20 days for delivery from the USA or Canada, 30 days from the USA.
Since today is Nov. 5 and you paid on Oct 19, we are at Day 17.
EBay takes its delivery dates from the postal service, who are .... optimistic.
Many sellers, especially those selling inexpensive items, don't charge their customers for tracking.
(It would cost me $5 to ship a paperback from here to ON without tracking, $14 for tracking).
And some are better at communicating than others.
However, you can go to the Resolution Centre at the bottom of this page and open an Item Not Received Dispute.
There may be a short cooling off period before this is activated, but you will have your foot in the door.