I think it's a low percentage that the pilot bearing/bushing would sieze. The issue is more of alignment because the bearing is too sloppy. If the first motion shaft doesn't line up with the crankshaft, it could put some undue tension on the front transmission bearing. Mostly, I think, you'll experience inconvenience in gear selection and, perhaps, some vibration in the drive-train. You can probably drive it around town for the rest of the year, but I wouldn't start a cross-country trip just yet.