The varmint gun is about a $50 upcharge from the standard model.
And no, $699-749 is not the price of a SPS varmint, that is the price Gander Mountain is wanting for them. Gander Mountain is notorious for having higher prices on their website than other stores, and even their store themselves. They are also guilty of price gouging.
A quick search of gun broker finds a varmint in just about any caliber from $530-750 while a standard SPS from $450-700, supporting the roughly $30-50 price difference from Remington.