They were based in Chicago, so they were HUGE with Chicago police and fire.
They where located in Chicago to early '70s when they moved to Naples, Florida.
When the company was sold to Tri-Lite in 1988 they moved back to Chicago.
The real Spectrasystems was made by Mars when they was Mars and located in Florida.
The Spectrasystems made by Tri-Lite was not so advanced as the Mars ones.
It is depending if your friends Spectrasystem is a standard bar for the civil market or one of the bars made for the US Army.
If it is a US Army bar it has plastic lamp holders and I will not say that it is worth as much as if it is a normal bar.
Then it depends what options it has internally, like 888's, lampheads with three sealed beams and flashers as the most advanced version had or only lampheads with two sealed beams and mirrors.
The bar is not common.