Gold Metal Models makes photo etched railings and ladders in N Scale
http://www.goldmm.com/
There may also be photo etched ship model accessories in 1/200 scale by Gold Medal or other companies that might work
I tried to sell my two cents worth, but no one would give me a plug nickel for it.
I don't have a leg to stand on.
Can anyone suggest a source for "catwalk" and "guard rail" material suitable for "city type" water towers in N scale?
Hiawatha Fan