I am Midwest born and raised and have lived in California, Colorado, and Arizona and I pronounce all 3 of those words exactly the same. Just a data point for you.
I have been sitting here trying to see how they might be pronounced differently and I can't. Can someone share a phonetic spelling of the difference?
Pronounce them how they're spelled? Ay as in 'nary' or 'scary' in Mary; 'eh' like Jerry in 'merry'; 'a' like 'carry' or 'tarry' in 'marry'.
May be relevant to my experience of this, almost everyone I have known is multilingual. As a Jew from a somewhat observant community, all my Jewish friends and relatives could at least pronounce hebrew by a young age, most could speak it by 13, for instance, and most of my other friends in new york as a kid spoke something else in addition to English, some spoke Italian, some spoke Spanish, some spoke Armenian, some Russian.
Learning to pronounce another language, especially one that is written in a different alphabet, does make you pay more attention to pronunciation in your own speech, so that may account for my experience. Hebrew speakers in particular have to be careful of vowels, as most vowels are not written in that language, you just need to know what vowel sound goes where.