German to English Art/Literary Livestock / Animal Husbandry 19th century novel

I'm proofreading a pre-existing translation and the section below is partially missing.

"Die Knaben gingen, der Förster setzte sich unterdessen auf's Bänkchen unter der Linde. Selbst wenn er schließlich auf dem Wege war, machte er noch halt und rief Großmutter zu: "Laßt Euch doch oben sehen, meine Alte hat für Euch Eier von **Tirolerhennen** zum Hühnersatz aufgehoben!""

The client says that it refers to a kind of poultry from Tyrol. I'd be inclined to leave it out except that if they're meant as a chicken substitute it probably matters what kind of egg they are. The previous translator had put "guinea eggs" but that makes me think of guinea fowl which doesn't seem right to me.

This is from a 19th century novel dealing with country life so a lot of the terms are probably obsolete.