Possible US Duplex Killer "16" On Canadian Stamp

Does anyone know if this duplex barred oval with 16 is an American cancel? The item is a small queen 3 cent stamp (1870-1897).

Thank you!

Hamilton, Ontario?

Brockville, Ontario. 16 was assigned to Hamilton earlier.

Thanks for the thoughts - would you have a reference for your suggestions? Any find these in my refs or online.

No need to duplicate threads. I just replied here.
https://goscf.com/t/91898#857650

But while I am here, rogdcam, would that Brockville, Ontario 16 cancel be the same style with a circular ring surrounding the digit, or the more common style with a square center?

Are we sure that the town assignments of 2-ring numeral cancels carried over to the later duplex cancels?

Not sure I understand the question. The cancellation we are discussing was used on the small queens. Are we going to later duplex cancels for some reason? See Unitrade pages 620-621 for a list of these numbers with City/Towns and rarity factors. Also, see BNAPS resources.

I was going to duplex cancels because that's what I assume is on the OP stamp. That looks, to me, like a date stamp to the left of the killer.

Whatever it is, it isn't a 2-ring numeral.

I'm going to sit back with a coffee and let others do research and report back. Look forward to seeing what you all come up with.

If anyone wants to go down the rabbit hole on these, Lowe calls the circle date stamp and killer on one hammer a duplex, which is a pretty common usage. (Encyclopedia Vol. 5 - North America]

Holmes, in his Specialized Catalogue, calls them "combined markings" and "combination markings" and you may want to use those terms in your searches, too, in case they were in wide usage among Canadian philatelists back in the day.

I'm not convinced that the OP cancel is Canadian. Maybe.

Hi all - again, thank you for the comments. I really enjoy when people offer their time to try to assist another hobbyist.

Not sure if this is a hobby "faux pas", but I concurrently posted a question on this item on Facebook, where I believe we have an answer

"Lacelle 126
D&S 879
Woodstock, ON (confirmed w the two remnants of the town fits)
MY87-JY91
Rate 2
With duplex dater, U.S.A. type, two varieties, month over date or vice versa. The "10" wears off in the late state. Duplex #DUN 165. See J175"

Have a good weekend!