Michael. This sounds like a furniture panel staining. It is a wood working job and the fact that it is on your boat is not material. Are you trying to make it a "perfect" match to the other wood in your boat? We both know perfect is not going to happen. You are going to have to try "best match" and perhaps blending. Think a ring stain on your dining room table.
If this is a new idea, consult a local wood refinishing shop. Try to bring a sample of good wood to them. They may be able to help you blend a stain that will nearly match. Remember your good areas are a mixture of original stain, cover coat (e.g. varnish), what ever cleaners or waxes you added, UV and air oxidation. To match you will be trying to mimic this stew of chemicals that are adhered to your wood. It is as much trial and error as it is getting the "Same" stain as was originally used. Just your luck you'll get the same name of stain and for what ever reason the manufacturer will have changed the formula to meet an EPA requirement and when you apply it, "You Can't Get No... Satisfaction".
Good luck and let the artist in you find a mix that will make your eyes smile.