I got these at a great price! 
http://www.anchorexpress.com/lees-tackle-ra5005sl-clamp-on-rod-holder Has them in stock in Sliver!!!
I like that set up !! I think it will work perfect for what I wanna use it for !!!
I use a 1" PVC -12" long for the base and notch out the bottoms so that it locks in the rod holder.
The I take 1" 45 degree elbow and a 1" to 3/4" reducer and glue them in tight!
Slide a wood dowel into the 3/4" PVC and glue a cap on the top. 
Drill 2 holes and in the place you want to attach the flag.
I have one pole that has a threaded connection - so that I can change out the flags.  I have a Dive Flag and a USA flag.  Besides the Dive flag all my other flags are 3' X 5'.
On my 2013 AR240 I did a similar set up and the flags could be flown at all speeds-  I could run wide open even with no issue.    I think this set up is much better.
I am so ready to spend some time on the water!!!!  Here is my flas on my AR 242 last year in Destin 

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