If there is a little room behind the lens, I might suggest using a theatrical gel material, which is really polyester MylarT. Lee Filters and Rosco Filters manufacture this material. It is also available through theatrical supply houses. The challenging part is to choose a color that warms up the light to your particular satisfaction. Some people like their warm light to be in the yellow range, while others prefer something in the peachy range. It also depends on the color temperature of the LEDs you have. They could be 4K, 5K or even 35K and still feel cool in color when compared to incandescent. I have a linear task light in my office that is 5K. I used the #154 Pale Rose by Lee to produce a hue I like. It brings a glow to my cheeks as if I’ve been freshly pinched by Aunt Vivian.