Anyone recognize this axle ?

I have this axle under a homemade motorcycle trailer, the guy I bought it from thinks it may have come from Chrysler product, maybe Dodge/Plymouth but isn't sure. I need to know what it came from so I can get new spindles when the time comes. ( I have one spare now )
Ths distance between the plates that the spindes bolt to is 54" and the wheels are a 5 bolt 4 1/2" pattern. the wheel studs are a 12x1.5 thread and are not left hand on either side.
I have taken the spare spinde to an auto parts store but without a part number they are lost. I have considered taking the trailer to some local salvage yards to see if anyone recognizes what the axle is from but I thought I would try you guys first.

Thanks

http://img46.imageshack.us/img46/4677/taileraxle006.th.jpg (http://img46.imageshack.us/i/taileraxle006.jpg/)

http://img194.imageshack.us/img194/6928/taileraxle009.th.jpg (http://img194.imageshack.us/i/taileraxle009.jpg/)

http://img130.imageshack.us/img130/1507/taileraxle007.th.jpg (http://img130.imageshack.us/i/taileraxle007.jpg/)

Here is a picture of the wheels if it is any help, I think these were the original wheels, anyways the hub fits real nice..

http://img251.imageshack.us/img251/9495/taileraxle003.th.jpg (http://img251.imageshack.us/i/taileraxle003.jpg/)

Not really seems to be good i will sure research on it more to get lot of information.