I use the glass MIXTUR bowls from ikea, they are very durable glass and look superb in the cage especially if you have a natural setup. They are actually oven dishes but I think the Medium and Small sizes would be too small for an oven dish, but they are a great size for sand baths., they come in three sizes but the large one is too big, I use the medium oven dishes for my Syrian's and they adore it. With the amount of space in the alaska it would be fine!
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MIXTUR Oven/serving dish - 27x18 cm - IKEA <- Medium(27 x 18cm)
MIXTUR Oven/serving dish - IKEA <- Small (15 x 15cm)