I was also very happy with the ride and performance of the original GY's that came on my 04 SE. I replaced them at 61K and, thanks to regular rotating, they still had 5-10K of tread left on them.
After doing some research (there IS a ton of discussion about tire replacements here) and shopping around, I opted for the Cooper CS-4 Touring tires back in 03/09. I just hit 90K, and the Coopers still look, ride and perform (including the past 2 winters of New England ice and snow) great. I found them locally for $150 each, including mounting, balancing and a decent road hazard warranty. The 4 tires netted to $590, after tax and a $40 Cooper rebate at the time. Since that was only 2 years ago, I'd guess you could shop around and find similar pricing today for the Coopers or similar replacements.
That said, the $203 you were quoted for the GY's isn't bad, though (as nitely suggested) it does sound a little high - especially for Walmart. Also, if you negotiate wisely, you should be able to get most places to throw in road hazzard coverage, especially if you are paying around $200/tire. And peronally, I'd never pay extra for rebalancing (rarely, if ever needed) or rotating (something I do semi-annually while I have the car in the air doing my oil changes).
Good luck. Let us know what you decide on.