They can restore your originals to original specs. I think it's in the neighborhood of $140, depending on what they find wrong. If you tell them what you have, they can tell you exactly which speakers match OEM. I'm sure I have their part numbers around here somewhere, but I'm thinking the repop front speaker is around $35, and the rear is around $50. If your radio still works, you could use it 'till it dies, or just restore it now. I think they can do conversions, but I haven't gone that route, so I'm not sure. They have done a half dozen radios for me now.

I have one extra original '68 AM/FM I could part with for the right price. They are almost impossible to find these days.