It's a bit of a drive from Castleton, but I've heard the Greenwood location has good selection. I go there every once in awhile just to get an idea of what's comfortable and they have a good selection if you can get someone to help you.
Don't forget you can buy from them online for a better selection and FREE shipping.
Centerfire Rifle - Model 700 SPS Tactical - Remington Centerfire Rifles. Remington Model 700 SPS Tactical, .308, Hogue stock. $700 at Gander, $600 at Buds and others.
Sell the gift card to someone for cash? Perhaps at a slight discount to them, then go to your local gun shop for some serious shopping?
Gift Card Exchange - Buy, Sell, and Trade Gift Cards Online | Cardpool
I use this site to sell off old gift cards I had or ones I didn't use. It is pretty easy just enter you amount and they tell you what they will give you for it and if you decide to sell it, you get a check in the mail from them.
This way you can get some cash to spend somewhere else other than GM
when the right gun goes on sale they will bring it down to about full retail ,that might be your only chance