Look into "Blue Valley Public Safety" in Kansas City. They buy and sell old sirens to communities and have a yard full of old sirens from the Kansas city area. If he's just trying to look at the sirens and get up close and personal I'm sure there's someone there kind enough to let you chec...
One thing I've always wanted to see is if a rotor with a size such as an STH-10 could be supercharged by some sort of blower. However I think a blower powerful enough to supercharge it would be impractical and uncalled for in a standard outdoor siren system. I'd still like to see how much you could ...
Check the kansas siren map, there's quite a few inactive in Topeka, KS and a few more in various smaller towns. I don't have the link but a simple search and you'll find the map easily.
Wichita, KS still has quite a bit of thunderbolts and still uses them along with many 130s. They honestly don't care about being up to date, and they wait til the sirens break before replacing them. Even for a clean college town, they don't seem too crazy about replacing the old sirens which is cool...
What's funny is that that thing has been sitting atop that building for over 60 years and it's working perfectly. Of course it might grow some rust and all but you should only work on fixing em' if they're broken. "Look how old it is!" it's not like anyone ever notices them except for us s...