..Those Unity Beacons are the same ones Karl Helcher had on his home-converted suburbans when we were kids. They were pretty good lights as I recall.
Unity still makes this light. It is available on their website along with parts and the bulbs. http://shop.unityusa.com/RV45R-H-Four-Lamp-Warning-Light--Red_p_1578.html
Kyle Supposedly The domes with the Stripes (Clear) are not available
The Guy who made the mixture to make these retired and took the formula
Russ