I changed out several incandescent festoon -type bulbs with LEDs if you'd like to do the same.
Here's a 561 at superbrightleds.com that is priced reasonably --$4.95 and you can choose different temperatures if ordering a normal white light (cool, natural, and warm) or different colors if you wish.
superbrightleds.com has a very good online reputation and I've ordered quite a few products from them through the years with good results.
561 LED Bulb - 9 SMD LED Festoon at superbrightled.com - $4.95