My well jet pump has been making louder than normal noises. Is it time to fix or replace it?

The screen is probably plugging up.

Actually, a much more likely occurrence would be that the bearings in the pump motor are worn out. This condition takes many years to get serious, as you can attest from the fact that you've been listening to it get louder and louder over the last ten years or so. Depending on what make and model it is, it can be a relatively straight forward remove the motor and take it somewhere to have the bearings replaced, or it can be a real problem. If it's a Flint & Walling, they are by far the best and most reliable pumps and motors around. Even at that, unless you've had some fairly extensive experience with removing motors from pumps, especially pumps that are still connected to a water supply, you would probably be ahead, possibly, monetarily and certainly in the peace of mind category, if you called a professional and had them do the job. The pump repair company you select may have rebuilt motors, which would include the new bearings and probably a start switch, ready to swap out with yours. The cost should be the same as though they took yours off, repaired it and brought it back and reinstalled it. The bearing replacement can't be done on the garage floor, so they have to take it back to the shop where they have a bearing press and the proper tools. IF it's any other brand, I'd call the repair shops and see what they think of what you have, and possibly get an estimate for repair. I doubt that you'd have to replace the whole thing.

Goulds Jet Pump Troubleshooting

Sounds like motor bearings to me also.If its a name brand pump it should be easy to get repaired.