Yes. It is. The original Sanskrit word is indeed आपूरà¥à¤¤à¤¿ But in Hindi all the short vowel at the end of the word become long. Hence should be spelt आपूरà¥à¤¤à¥€
ummm...That's a bit confusing. I often use a dictionary to confirm about small/big i and u. I've checked google and shabdakosh (http://www.shabdkosh.com/s?e=supply&f=0&t=0). Even my Hindi into hindi into English dictionary uses small i. Can you verify your claim?
Yes. I have given you the explanation why the last vowel should be long. Please do not rely too much on online tools & dictionaries. They may used as references or a starting point but none of them is fully reliable.
since drkpp has agreed that आपूरà¥à¤¤à¤¿ is a better substitute than सामगà¥à¤°à¥€ and the only confusion is about the small or big i, I'll edit it. I'm going to use small i because exceptions are always there and specific forms take preference over generalized rules. Since all the dictionaries (paper/electronic) list it as आपूरà¥à¤¤à¤¿ I'll use that form.