Ok, that I can answer
it definitely is a 194/158/165 type bulb in the license plate. I also had a Putco one that started to flicker in there, and when I went to take it out the damn bulb lens clip broke, so I had to order a new one from Amazon
... anyways, I ordered a new one from V-led and chose the flank model as the light in the license plate should mainly be directed downwards on the lens .. it looks ultra cool btw .. I will take some photos for you if you want, this is the ones I got, unfortunately they are on back order too, worth the wait
5K WHITE 4 LED 2 WATT HP FLANK BULBS 194 168 158 | 1 PAIR (BACKORDERED MID MARCH) B/O - 5K White LED - 194 - 168 - 158 LED - Shop Bulb#
For any future bulb size, I would refer to Jeep Grand Cherokee WK - Lamps & lighting
where you can find all the specs you need. The only thing wrong about this the spec of the reverse lights, they are as per the US model and not export.