I have a 1957 F-100 with the 223 I-6 motor and Holley single barrel carb. My question is

On the top of the float bowl there is a small opening that looks like a raised hole with two small openings on the side. Inside that hole there looks to be some type of plug.

Well my plug is no longer in that hole and it is pumping a steady stream of gas out of it. I looked at a bunch of rebuild kits but none of them look like they come with any type of plug for that.

What do I do? Is there a place to buy that plug or do I just make one with some epoxy? Any info or fixes will be greatly appreciated.