Take a cover off one you have and head to the auto parts stores or a truck stop. The truck stop will have several different styles not sure about the auto stores. The bulbs likely a 168 mini very common in markers.
2000 F250SD SRW 7.3 Long Bed Extended Cab Air Bags
2014 Eagle 30.5BHLT
2007 Layton 245LF (sold)
196? Shasta 16ft
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