I'm searching for a new fuel pump and I'm curious why all the newly manufactured ones are missing the glass bulb with the fuel filter in it? Is there a seller that has the original design for sale?

The fuel pump that you are looking for is the one that originally came from the factory on early Y-Block engines.  If you want the double action pump with the vacuum booster for the wipers,  you need an AC Pump # 4315.  Here is an NOS rebuilt pump, probably from the 1960's for sale on EBAY.   I know that some people will tell you not to buy one of these old rebuilt pumps as the seals may have dried out or they are not fit to run on our modern unleaded gas.  However, I have bought several of these older rebuilts over the years and I have recommended to other people that they buy them and I have never bought a "dud" or had one fail nor have I heard about one of them being no good.
https://www.ebay.com/itm/166616218780