This Ballast is no longer available, and I need help with replacing it

Hi Harrison,

Have you considered doing without the ballast? There are two types of replacement LED bulbs for florescent fixtures; one that works with the existing ballast, and one that works directly off 110VAC and requires removing the ballast. The latter kind would be a perfect replacement for your situation since you have to take out the ballast anyway in order to use them. I ran across a page that describes the LED options available to you here.

T8 LED Tube Lights - Commercial LED Tubes

You can buy them everywhere; here's an example.

HALCO LIGHTING TECHNOLOGIES 4 ft. 14-Watt T8 Non-Dimmable LED Linear Light Bulb Type B Bypass Double Ended Daylight 5000K (10-Pack) T8FR14/850/BYP3/DE/LED10PK 89003 - The Home Depot

Obviously you don't need 10 of them (or maybe you do, I don't know), but that's just to give you an idea of what kind you'd want; the first link I provided calls them "Type B" LED bulbs, as you see in the text of the second link.