I built my own ice kit for my striker 4 a few weeks ago. It was super easy and saved me a fair amount of money. Originally built a transducer holder using PVC, but decided after a few trips to just spend the money on the official ice transducer to save space and for ease of use.
I used a plastic ammo box to store my battery, transducer, tackle box and other small easy to lose things. I mounted the bracket for the Striker on the top of the box and I take it off and store it inside of the box when I am not fishing. I'd estimate I have spent a bit over 200$ overall, which is not too crazy IMO. Feel free to reply with any questions.