I personally would look into other options than Amazon, but if your determined to spend your gift card I would try and go modular and buy it by the piece.

Edit: this is an actual reflux column and will fit on a keg, but its not the best/most efficient design.

https://www.amazon.com/Moonshine-Stills-Stainless-Reflux-Column/dp/B00OZXUXW8/ref=mp_s_a_1_3?dchild=1&keywords=reflux+column+still&qid=1622758687&sr=8-3

Second edit: this is a modular package, a bit more expensive than piecing it out but less hassle.

https://www.amazon.com/PPFT13327-Distiller-Distillation-Moonshine-Sanitary/dp/B08P467DLK/ref=mp_s_a_1_17?dchild=1&keywords=reflux+column+still&qid=1622759091&sr=8-17