I made some final progress on the siren today. I put the siren back together using stainless hardware on both the shroud and housing. Here is how the siren looks as of tonight. I, as promised, will take pictures of this guy in some sunlight tomorrow. Until I get the necessary components to get this siren working again, this is as far restored as it will get.
And for once a picture comes out right from my phone! Woo hoo!