For trying to convey this concept, cannas or tagol/tegyl (vs. *or–/hal–chen(neth), –chened "elevated vision") might also be a sensible element, combined with dôr/dŷr or gardh in some manner; cp. Goidelic Celtic dealbh-dùthga.

The reason I thought of parlas was because of the etymology of the word for "map" in my mothertongue, where it's a derivate of latin charta. *orchened sounds more like "outlook, view from elevated level", or even "surveillance", like if one has climbed a tree or a tower to look out.