So it's more about room than wallet I am assuming.. as a 10g full kit is only $10 more. I can understand the space issues.
Hmm.. I know my Walmart sells 10g complete kits for $30 - got one for just plants. Oh well.. they do have this tank.
The tank you just posted isn't the greatest, but it can house them safely and healthy. With substrate it will give them about a gallon each - which tends to be the recommended bare minimum per betta. They can still see each other, has a filter which will help. Heaters generally are cheap - look for a 25 watt one for that size of a tank once you are able to.
For now, and for a good while they should be fine in that tank. Just make sure to keep up with the weekly water changes though, as it's still rather small for 2 fish. But it's better than them sharing a smaller tank with no divider.
If you get it before you leave for Ohio, keep one girl in the 1.5 and another in the new tank - that way the water won't foul up so quickly and there is a better chance at them surviving.
Can also check on Amazon.com - tend to find the same items much cheaper there :)