Im in the uk and ive used these Heatsinks with no issue at 50w passive with general air circulation
https://www.amazon.co.uk/gp/product...b-0822-4044-bbe9-441718232b3f&pf_rd_i=desktop
And these look to be pretty cheap for the citi leds
https://m.ebay.co.uk/itm/253122654528
https://www.amazon.co.uk/gp/product...b-0822-4044-bbe9-441718232b3f&pf_rd_i=desktop
And these look to be pretty cheap for the citi leds
https://m.ebay.co.uk/itm/253122654528