I think the idea is too far fetched. Ethereum's price do struggle to break or even reach $450 as of today. Also, if Ethereum's price changed that much expect bitcoin will be priced at or almost $10000. The idea of Ethereum having $1000 in a span of 2-3 months is way too absurd. Maybe over the course of a 2 year period not a couple of months.
I think the price of ETH and BTC will be $1000 and $10,000 respectively.
I believe only time will tell if that ends up as mentioned by you. ETH may see a huge push after its HF, apparently which looks like it is going to be successful.
This upgrade will bring a whole lot of development and make us to see a new era for ETH, $1000 in ending of this year really seems impossible but who knows? It is cryptoworld and surprises are just always around the corner.