Reference for Parah 2:1
רַבִּי אֱלִיעֶזֶר אוֹמֵר, פָּרַת חַטָּאת הַמְעֻבֶּרֶת, כְּשֵׁרָה. וַחֲכָמִים פּוֹסְלִין. רַבִּי אֱלִיעֶזֶר אוֹמֵר, אֵינָהּ נִלְקַחַת מִן הַנָּכְרִים. וַחֲכָמִים מַכְשִׁירִים. וְלֹא זוֹ בִלְבַד, אֶלָּא כָל קָרְבְּנוֹת הַצִּבּוּר וְהַיָּחִיד בָּאִין מֵהָאָרֶץ וּמִחוּץ לָאָרֶץ, מִן הֶחָדָשׁ וּמִן הַיָּשָׁן, חוּץ מִן הָעֹמֶר וּשְׁתֵּי הַלֶּחֶם שֶׁאֵינָן בָּאִין אֶלָּא מִן הֶחָדָשׁ וּמִן הָאָרֶץ:
Rabbi Eliezer says: A pregnant <i>parat chatat</i> [a red heifer used for the purification ritual] is valid [for the ritual]. And the Sages invalidate it. Rabbi Eliezer says: It cannot be purchased from gentiles. And the Sages validate [purchasing a red heifer from gentiles]. And furthermore all communal and individual sacrifices [may] come either from the Land [of Israel] or from outside of the Land, either from the new [grain, harvested in the new year but before the omer sacrifice is brought on Pesach, and forbidden until after the sacrifice] or from the old [grain], except for the omer and the two loaves [offered on Shavuot] which may only be brought from the new [grain] and from the Land.