Extension sticker on green card vs. I-551 stamp in passport

[erst]

Hello, I'm a citizen of India and my green card is expiring soon (it's been 10 years). I applied for a replacement in January and it apparently takes over 9 months. At the biometrics appointment in February, I got a sticker on my green card extending it to November (but not inclusive of Novemeber, as I understand). I'm intending to do some international travel right around that time so if I haven't received my green card by then, that's a problem. I recently called and they're still processing cases from last July so that's a very real possibility.

I've read that I can use "Infopass" to schedule a meeting and get an I-551 stamp that's valid for a whole year, which is a lot better for my situation even if it's only a few additional months. I'm not afraid of being let in to the country by an immigration official since I know PR status continues past card expiration -- I'm more worried about the airlines not letting me board the plane in the first place. My card still has a month of its original expiration left and I've already gotten questions from airline check-in counters about it and had to point out my extension sticker.

So my question is: can I get this I-551 stamp despite already having the green card sticker? Is it fully equivalent to having a green card?

[Jot18]

You can get a stamp on your passport but however if your GC doesn't expire until Nov, I highly doubt USCIS will give you another stamp on your passport. Because that'll be more than 6 months until expiration and you shouldn't stay out of US for more than 6 months continuously. For that sticker you just make infopass appointment and they'll give you a sticker on PP.

I also applied for GC last year due to a name error which I never got it fixed since I came here in 2007. I applied around last week of April 2014 and just received my card on Feb 23, 2015.