Hi. I am looking to purchase a series 45 Horizon depth sounder and a series 45 knotometer. However, it seems that Horizon has discontinued this series lately. I am hoping that you folks might know of some that are on the shelf or for sale used in good condition. My Cat 30 has a set of these but they are quite worn and need replacement. These gauges fit a 4" dia opening and have a 5" face. Any insight/advice/information would be greatly appreciated. Thanks John