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

Welcome here!

Buying a carb kit on RockAuto (or any other regular parts store) is a recipe for failure and disappointment; mass-market carburetor kit quality and completeness are awful these days. Spend the extra money to get a much better kit from Jon Hardgrove at The Carburetor Shop. Yours has all the hallmarks of being a 1969-spec carburetor (the spring-staged compound choke lever, the idle air bypass column, the throttle body anti-ice system, the slow-closing throttle dashpot. The carb ID tag is missing, so this might or might not be the car's original carburetor, but it is certainly close enough that if you order a kit for the original carb type (Carter BBS 4601s) you'll get exactly what you need. Check with Jon to see if his kits still include float gauges; if not, see here.

Carburetor operation and repair manuals and links to training movies and carb repair/modification threads are posted here for free download. Tune-up parts and technique suggestions are in this post.