In regards to the light bulbs I was able to find an original style replacement for my Fisher KM-60 tuner but your receiver looks like it uses bulbs with different dimensions than the part I used (longer and skinnier?). In any case here is the link for the one that worked for me. Perhaps that might spur a hunt for something that will fit yours.
6V 3W SV7 8 x 36 MM FESTOON BULB CAR NUMBER PLATE INDICATOR INTERIOR LIGHT LAMP
Check the dimensions on your bulb and the voltage that it requires. The one I used wasn't painted white to direct the light, but I'm sure that you could add that to any bulb.
BTW, the link is for an international seller and if you thought that shipping international was slow before the current disturbance - wow you should see how long it takes now! I bought some hair clippers from the big retail site and didn't know that it was coming international. It took 3 months! I did get reimbursed, but that's much too long. The big auction site will generally tell you if it is international. The big retail site generally will not tell you, but they estimate shipping time (usually) and if it goes much longer they will often refund your purchase.