You should be able to make fine starters with out needing a stir plate. I use a 1 gal jug, an airlock, and a whisk for aeration. I make a the starter the day before and pitch the entire volume into my wort. Using this method I've reduced my lag time and cleaned up some of the off flavors in my beer.
I think the best use of your gift card would be to buy the kettle and then find a good procedure for making staters.