This far in advance and without ready upgrade instruments - I would just watch for a huge business class sale. If you are not limited to *A the chances to catch a reasonable price are quite good. I am not familiar with fares to India so can not give an estimate of what to expect though.
Creative routing might help sometimes. For example fares from Canada might be cheaper and it is just a short and inexpensive hop north from ORD.
There are plenty of information on different cabins, look at SeatGuru or another similar site.
Upgrades for cash happen sometimes but it is a lottery. You would not know until the last moment if you won it. Upgrades by paying a fare difference - you might need to pay a change fee of $250 (or more) on top of the fare difference. Whether it makes sense for you is for you to decide. You can buy a cheap economy ticket and consider that you have bought an insurance for $250 that you will not have to pay through the nose if fare rises. The huge drawback - you are limited to the carrier for which you bought the economy fare. If another carrier (e.g. AC) publish a low business class fare you are out of luck.
Upgrades with an instrument might be an option. After all you can buy miles you need to upgrade. But then it is again a lottery with the upgrade space. Without elite status, on UA your chances to win this lottery might be low.
A huge drawback of upgrades with instruments on UA is that in case of any changes or IRROPs you loose your upgrade. You are not considered a business class passenger just an upgrader.
My personal choice for such a trip would be to go with BA. It is not a *A however. With BA you can buy a premium eco ticket and then upgrade with miles to business. Currently they sell the cheapest premium economy from ORD to DEL for about $2500 all in. Even if you are not a member of their FF program you will get enough miles to upgrade your trip just by signing up for a Chase Visa card. And once you are upgraded - you have a business class tickets so any *involuntary* changes preserve your business class seat. But! This is just my personal experience.
I believe some Asian airlines offer premium economy fares, so you might consider that option too.