There are a couple of options for a large, non-backlit, low power display that are less expensive than the e-ink monitor they're using. One is the Samsung EM32DX, a 32" color e-ink digital sign for <$1300 (<$1000 if you can find it on sale) but it has a long refresh time. The other is the SVD rE 32" reflective LCD monitor for ~$1000, but it needs to be in brightly lit rooms because of its low contrast.