there are several bars that have what is in effect a width adjustment. Go to amazon and search “miter bar” You’ll see ones from micro-jig, rockler, Kreg and others. You can also make one from wood or UHMW
Greg, I have 3. A 1400 with the shelf holes, a regular 1400 and a regular 1080. You can have any one of these for free. Actually, I guess you can have the regular 1400 and the 1080.
But you’ll have to figure out a way to get them.