old ALKCO (?) lighted EXIT sign

The euro-exit light I posted last week got me thinking -- it is my newest, but not nearly *only* exit light in the collection --and I hadn't shown any of the rest yet. So here goes with them...? :-)

Guessing this one dates from the 1950's, maybe a little earlier. Got it from eBay several years ago for cheap, because nobody else bid on it. ;-) Its painted sheet metal enclosure box features a pair of hinged 'doors' that unclip to open on one end, to allow the glass front/back panels to slide out and in turn gain access to the two standard porcelain light sockets inside, only one of which currently has a working 11w 'sign bulb' in it.

It measures roughly 11" x 7" x 4", the only discernable mfr's info is on the one of its glass panels that still has the EXIT lettering on it, reading "ALKCO MFG. CO. CHICAGO, ILL.". I don't know for sure whether this was who made the fixture itself, or only the glass panel(s) -- the other glass panel only has the slightest few flecks of remaining red paint from whatever legend it once read remaining to be seen.