https://www.canadiantire.ca/en/pdp/round-boat-stern-light-base-0792468p.html
Round Boat Stern Light Base | Canadian Tire
This round, stainless steel stern light base from CTC keeps your pole light secure while ensuring your boat's back deck looks shipshape. The handy cover...
stern light baseroundboatcanadiantire
https://www.bonanza.com/items/like/1733391166
Perko 1069P00DP Stern Bow Pole Light Base 2 and 50 similar items
Priced $19.75. Perko 1069P00DP Stern Bow Pole Light Base 2 Contact 2-1/4" round
pole light base