Where to buy Holle formula?

Hello, I recently switched my son to the Holle formula infant step one. He is three months old, and we mix it using the baby Brezza.

I bought 12 boxes straight from Germany through the violey company. I had to pay for shipping and customs to Canada. It cost about 16$ Canadian per box.

I am looking for advice on 1) what websites/stores offer the cheapest deal when bulk buying and delivering to North America (Canada specifically), and

2) does it matter how the formula is shipped overseas (how it is packaged, e.g. climate control issues)?

Thanks!