No matter how many fenders I deploy, the cheap plastic engine vents on my '87 390 EC are frequently struck by other boaters during rafting and lock passage. I have queried the Internet trying to find exact stainless replacements to include the mounting holes. I don't like making extra holes in my boat. There are many stainless vent sources but but none have the exact features. Even the custom made sources are reluctant to tackle this request. Or should I just continue to purchase the available vents from Sea Ray? Is there an exact replacement available?