"Oilite" is from the name of the first company to make porous bronze bushings. Like other trade names, it has become synonymous with the bushing type, regardless of who made them. The generic name is "Sintered Bronze".
Felt plugs weren't added by Atlas until just after the 101.07301 went out of production. But I would recommend using them as they will reduce oil slinging and tend to protect the bushings if you forget to top up the oil before starting the motor one morning. They are relatively low density felt about the diameter of the large end of the cup and of a thickness such that after installing them and filling them with oil, they come right to the top of the cups. It is not necessary that they have two diameters and continue through the small end of the cup. You can buy felt sheet and the proper diameter arch punch but arch punches aren't cheap and the minimum amount of felt sheet that you can buy will be enough to make about a bzillion of them. Clausing still sells them but you need to be needing more than just a few felts or the shipping will cost much more than the felts. They use UPS, who have a 1 lb minimum charge.