You can order direct from Burpee if you really like that variety. Under $10 with a code, which is still expensive for a pack of seeds, but is what you want.

https://www.burpee.com/corn-northern-xtra-sweet-hybrid-prod000671.html

The 200 seed packets are in stock.

honestly there isn't one you will find at a box store. My "go to" varieties were peaches and cream Se (70 days) or Bilicious Se (80 days) and are good and usually available in box stores. I've tested everything offered in those displays but my "go to" varieties were always better, until 4 years ago. I order only Nirvana sh2 (72days) now and it blows away anything I've ever had!

Over the years my neighbor and I would each buy a different seed variety to grow and try along with our "go to" favorites (but not beside and at least 200 feet away from each other) with nothing better but 4 years ago the neighbor tried Nirvana. We were all shocked how damn good it tasted! Perfect 8" full ears of nice kernels that pop full of sweet corn flavor. I highly recommend this corn as the best and if you do consider ordering a pack you won't be disappointed, my neighbor and I bought 1000 seeds this year.

We like Ambrosia. Burpee's sells it a 200 seed pack by mail order, but you may find a local store selling Burpee's seeds and if so the size of the package will be smaller and it'll be cheaper. The big box stores used to stock Burpee's but don't anymore. My local hardware store (True Value) does though, so look around.

Robert you are right! I checked and got confused and the 200 seed packs were out but 500 were in stock! DOPE! Everyone else thanks. VERY tempting to try some of your ideas but Burpee northern Xtra sweet hybrid was crazy good. Every single person who tried it said it was then best sweet corn they had ever had. I cannot imagine anything better and would be salty if I tried something new and did not like it.

I do not have room to plant 2 different kinds.

Home Depot lists Northern Xtra-Sweet (Gurneys' label). It is an older hybrid of the X-tra sweet series and pretty wildly available. Check online vendors as well. It is not an exclusive Burpee variety