I have little doubt that you could buy a matching ST-60 depth display, and the transducer. If not new, they often come up for sale used, at a very reasonable price.
I had ST-60 wind, depth and speed on Skipping Stone.Wind required occasionally replacing the transducer aloft, the depth worked very nicely w/o any attention, but the speed through the water never worked, nor did I care. I had all that and more on my chartplotter.