Good call - I could see ice becoming scarce by that point around your base - especially if you're growing lots of plants in greenhouses.
I have a Weather Manager half setup. I suppose I should figure out how that could be used to replenish the world ice tiles over time.
Thinking out loud to myself here... could be like:
Rain storm deposits water puddles scattered around the planet surface -> that after a few minutes have a chance of "freezing" into collectible ice tiles. Or maybe there's some other base module / tech that lets you generate water (like an underground well, or moisture vaporator like in Star Wars)