I need a prop for my new to me, 83 Johnson v4 115hp, that is strapped to a 16' bass boat.  This is my first boat and have rebuilt the entire fuel system.  It runs good but the prop is toast.
 
The prop now is spun out and after 3000rpm slips.  It has one blade tip missing also.

What was the stock prop?  or did you specify your prop from the dealer?

Guy at marina said that newer hub systems are the way to go.  Merc sys I think?

I have no clue as to the current dia-pitch.  

Isn't that typically cast into the prop?

yes,  but Im at work browsing the prop sites   and dont know my current prop.

yes,  but Im at work browsing the prop sites   and dont know my current prop.

Would about 19" pitch seem standard for a bass boat?

Buy whatever you want but I'd check what pitch you are running right now.

Pitch and diameter is usually stamped on the side of the prop, on the hub, or it's "coded" in the part number cast into the hub. This means you need to look up the part number to determine what it is.

I'd start with a 17 pitch and go from there if you don't know what the existing prop is. Problem is, that you may need to try several props until it's "propped out" correctly.

Finding a local shop or marina that would allow you to test several props would be ideal, but they are few and far between.

You may see if a local shop would allow you to buy two or three props to try out, then return (undamaged of course) the ones that don't work for you.