in case anyone is interested, the festoon bulb size for the map lights are 43mm. i just got some nice white ones via ebay and put them in and they look great.

waiting for the 38mm ones to arrive to put in the rear passenger lighting area

 

Since landscaping lights use same voltage and there are lots of them readily available and cheaper, I use them in my car. Most of them are direct replacement and some may need minor modification. You can also pick different color temperature to fit your taste.