[ARC5] Help Identify This Shock Mount

[Nels Anderson]

I'm helping an elderly ham friend clean out his basement and we found a 
shock mount base that we cannot identify. It looks like a WWII era 
aircraft radio mount of some sort. Initially we thought it was for a 
BC-348 but while the size is right the fit is not.

The size is 18.5 by 7.5 inches. Please see the photos. Can anyone 
identify what radio this is for? After we identify it will be for sale 
if anyone is interested. Thanks for the help.

73 Nels K1UR

Photos:

http://www.trainsim.com/ebay/mount3.jpg
http://www.trainsim.com/ebay/mount2.jpg
http://www.trainsim.com/ebay/mount1.jpg