Looks like you found a 56 in good condition. Looks like all the hard to find pieces are there.
As for the fin color there is no absolute answer, but from all the pictures and boats I have seen I believe they were not painted at the factory.
I have attached two scans from the 1956 Herters marine catalog. It says that the boat was available in red , black, or green. A single color or any two colors could be used on the deck and hull. It appears this boat has one color on the hull, another on the deck, and the fins another color that appears to be aluminum.
That said, it also appears that the fins may have been airbrushed on. A possible reason may be that the catalog was made up well in advance of the boat's availability, and the fin castings may not have been completed yet. There are a number of examples of airbrushed photos in the Herters catalogs.
If it has been airbrushed it looks they did not try to match one of the hull or deck colors indicating it was intended to be natural aluminum.
Bill Anderson has a very nicely restored 56 and I believe he may have also tried to find out if they were painted, but it looks like he went with a natural finish. You may want to look at his posts on the restoration for more info.
Sorry, I am having trouble posting a JPEG, 800 KB pic. Never had this problem before. Will try to get them posted later.
Here is mine,,I just buffed them then cleared them,this is my favorite herters of the fleet,,I don't like the way they handle til 58 when they changed the hull,,the old ones flex to much for me,,I stiffened my 57 with balsa wood,it helped a lot,,just my opinion Bill
Thinking more about the fins.....I like Bill's idea of clear coating them. I'm used to using a self etching primer on aluminum, like zinc chromate or self etching primers. How would I prepare these aluminum fins to be clear coated? Also considering leaving them bare.
That is a very common problem. When I rebuilt my Herters I just removed all the commotion of that transom an installed a new wooden one. ...unless you want to keep it original. There are pics on this site somewhere but it was a few years ago.
A 1956 Catalog listed 40 HP but an ad sent to a boating magazine said 50 HP. for the full named - "Herter's Chrome Fiberglass Duofoil World Famous Flying Fish Runabout" ....... Try putting that in the Model box on a DMV registration form....
If you decide to go with a wood transom it will need to be at least an inch and half thick (two 3/4 plywood pieces) and it will have to be attached to the hull with at least some glass and resin.
Then if you want to use the original transom later the transom will be too thick for a motors transom clamps.
If you don't mind chiseling out the temporary transom it can be done, but if you want to use the original I think you should get it repaired and put in from the start.
There are a number of things that can be done to beef up an original.
The first pic shows a single 1/2 piece of plywood glassed in and covered with cloth so it looks like the original hull. Then mount the original and you have about an 1-1/2 transom and it looks stock.
The second pic shows a heavy piece of aluminium that was machined to fit across the top and rear of the transom. the vertical leg was about 1/2 inch thick and six inches deep. It was bolted through the the original transom. You may have to add spacers if you can't drill through the transom in the web areas. (third pic)
Then if you are using the original transom make sure you have the original Herters knee brace installed. (fourth pic) If you don't have one you can fabricate one or I have seen double wood knee braces glassed in.
Thanks for the ads, alumaglass. "Hand cast duraluminum, resinote-bonded fiberglas, epofoam floatation units enclosed in tanks".....and it's guaranteed to be the fasted 15 ft boat on earth. The Herters Hyperbole Department was running hot that day. My "epofoam" is styrofoam stuffed up under the deck. Seem to be original as they are formed to fit.
Good point on the transom fix, Don. The boating season is short in Maine. I guess I've been looking for a quick fix so I can run this boat this year.