I had the same speakers from the factory in my boat. I tried to buy replacement clarions, but the tweeters didnt fit in the factory cut-outs for my X-80. The main clarion speaker was fine.
I ended up replacing all the in-boat speakers with Polk Audio 6.5's and the tweeters for the in-boat speakers fit perfect (not the towers).
I bought these on Amazon: 3 "Polk Audio DB6501 6.5-Inch 2-Way Component System (Pair, Silver)"
Electronics; $109.45 each set
Sold by: Central Buys
They fit perfect in the stock locations and sound great for the money. I have Wetsounds Rev10's on my tower...so no need to be crazy in the boat. I have an X-80 and they are clean and loud all throughout the boat.