Looking for carburetor ID on euro spec 1969 Plymouth Valiant Signet 170

That is a Carter BBS. (Ball and Ball single barrel) No way to tell the exact model without the tin tab attached to the missing fuel bowl screw. The kits cover multiple years. Just match the old gaskets with the new ones. I think the metering rod that goes into the jet is different from the different applications. They never wear out.

Check the play or sloppyness in the throttle shaft. It will cause a vacuum leak. You can install bushings.

There is Chinese copies of these carbs out there. I have no experience with them.

https://www.slantsix.org/forum/viewtopic.php?t=33102
https://duckduckgo.com/?t=ffab&q=carter+BBS+guide&atb=v389-1&ia=web