[wardmc1]

I'm pretty sure it's a model 507, but I have been wrong before.  Some Radiobars did come without a radio, so yours may have come without one from the factory.  I would be suspicious about the accordion style doors, they may be an add on from a previous owner and not original.  Look at the attached picture here, the owner of this 507 fabricated a wood speaker mount.  I guess the original grill had been destroyed and this was their best shot at fixing it.  I would take the time to fabricate the correct panel.  Making the correct veneer would be difficult, but not impossible. Below is a picture of one with the correct panel for reference. Definitely post some more pictures and hopefully we can answer any of your questions