I danced around gold-parts-or-not when I had my Elan built; ultimately the brass bits were traditional Alembic and I went thataway. The truss rod door, the back plate, and the bird tailpiece are clear coated, so they never have to be Flitz'd.
The brass bridge you'll find will usually have to be completely disassembled (make a diagram first!) every 12 to 18 months to stay as shiny as the coated stuff, along with the nut and the logo-piece, if it's not one of the nice counter-sunk ones. There's any number of polishes that work fine with brass. Afterwards the VO5 is a great coating, and I lube the threaded bits with BreakFree CLP.
I took the cheap way out with the gold look, though: I got gold keys, which look great with the brass parts. Somehow, the chrome keys just did NOT look right to me with the brass bits. If you have chrome keys, you might consider this, I'm sure it's cheaper than having the parts removed, plated, and re-installed.
Alembic's usual practice is to plate the nut and the bridge AFTER set-up, so that the grooves are also plated. This prevents that string to raw metal contact that eats up so many gold bridges on other guitars.
NICE Koa.
J o e y