I did find your machine on the ISMACS needle list, and they agree that the manufacturer is Williams, it's going to take a Singer 4x1 needle, or the Boye 8 needle, it doesn't list a shuttle. For your slide plates, check with Jenny at sew-classic.com, if she doesn't have them, she will probably know which way to point you to get them.
I have a few NOS shuttles but am not sure that they'd fit your machine. Most of the time, if you can get fairly close to the original in shuttle size, it will work. (Nice thing about these old girls!)
Check with the ISMACS group (send an email to their list), you might also join Needlebar and see if the guys and gals there can help!
ETA: I apologize for being a "know it all" and saying that the machine was a badged name!!
I should have done a bit of research first!