accelerator pump

Hi all
( please don't ask why i want to know) hahaha

OK, 74 dart 318, has a rebuilt carter BBd 2bbl
it has sat for some time now.. the accelerator pump was not working
I bought a rebuild kit, the kit had most of the correct parts, except for the "top" gasket
and the "accelerator pump".
the one in the kit has a smaller diameter "head"
Why?
I've been reading and I find that these carbs have either a short or tall style?
I installed the old pump and of course it's not working...
last night on ebay I bought an accelerator pump. hoping it will fix my problem

But I'm at the point of buy a replacement carter BBd for this engine.
can anyone tell me which is the correct carb to buy. I know there are many
"parts" numbers.
the car has an automatic trans..
or should I buy a Holley carb?
I don't care if it's stock or not, just getting it to run..
Best