VRO 150 Ocean Pro

[Joker2]

I think I have determined my noisy rattle, I finally got up the nerve to rev the engine up to 3500 in nuetral to see if I heard the noise, and yes I did, I am really afraid now that it is internal and not something loose while underway. I think it may always be making the noise I just can't hear it at lower than 3000 or higher than 4000. What would I be looking at price wise to have a mechanic open up the block and check it out? I hope this is not a complete nightmare. Thanks