looking for bbs3767s.Manual trans carbs. and bbd3843s,wwc3243. Manual trans carbs.
The Carter BBD 3843s is a 1965 273/manual carburetor. The 3767s you mention is a BBD (1964 273/manual), not a BBS (the BBS is a model of 1-barrel Slant-6 carb).
Bendix Stromberg WWC3 carbs were big (1-1/2" mount) 2bbl carbs not used on small V8s, only on big V8s (361 and up). The smaller (1-1/4" mount) WW3 carbs were used on small V8s.
"Remanufactured" carburetors—of any description—are almost always unworthy junk. Same goes for the "100% New!!!!!!!!!" Chinese knockoff BBDs all over the internet (tipoffs: often marketed as "high top" or "low top" and fraudulently claimed to fit a giant range of model years).
And when the cast in #'s arent there ,what other #'s can be crossreferenced to match?
On a Carter carb, none. The applicable numbers weren't cast or stamped into those carbs, instead they were stamped on a little aluminum tag attached by one of the bowl screws. Once that tag is removed or broken off, the carburetor can no longer be definitively identified.
The Bendix-Stromberg carbs have their numbers stamped into the airhorn (top casting).
There are calibration differences in carburetors intended for use with manual versus automatic transmissions. How much does it matter? That depends on the particulars of the car and carburetor in question. Sometimes it doesn't matter at all; sometimes it matters a lot. Also, there are physical differences in '65-down versus '66-up carburetors, notably the air cleaner attachment provisions, so at some point in picking a carburetor you need to know (or decide) what air cleaner assembly you're going to be using.
I might still have a few new-in-box Bendix Stromberg '64-'65 WW3 carbs; send me a PM if you'd like me to go dig around on the right shelves.