Orlak is scarce but, like all glass, it really depends on the condition as to how valuable it would be to another collector (and this is determined by how much they are prepared to pay – no more, no less). However, oven-to-tableware was not always treated with the same respect as art glass, so mint condition pieces are not common at all!
Do you have the pattern number? It should be one or two letters, followed by three digits. The lid might have a different number. Also, some dimensions would be useful for my research, and photos would not go amiss either.
A typical number would be W203 (circular side plate).
However, since writing the book, I am finding that a few more pieces are beginning to surface, including a mint item with label (so never used) that will shortly be offered on the Glass Market Place.