If you know the voltage rating and the capacitance rating you can narrow down where it goes pretty easy. On top of that it should not take too much examination to find the remains for that cap on the board. Imagine if you will the case from your lead acid battery in your car fell off and all you had in the car was the internal guts from the battery still hooked up to the cables. This is similar to that.
Something is being effected just because you can not tell does not mean the radio is functioning normally. It just means that single part failure has not caused enough damage yet to become obvious to you during normal operations. Same thing happens in car's and in people where something is wrong but not presenting enough symptoms yet to be discovered by mechanic or doctor with routine test's. That is when you have to wait for it to get worse before you can figure out what is wrong!
You should take this radio right away to a good radio technician because those are really good radio's and their is nothing like them today. Parts are almost unobtainium!
