The Skino 705 doesn't come in the sizes you need, but you can get the Kenda K761, which is more or less the same type of tire as the 705 made by another manufacturer, and it does come in a 120/90-17 and 100/90-19
http://powersports.kendatire.com/en-...61-dual-sport/
If you go on a website and only see a size listed as rear, like the 100/90-19 K761, just keep in mind that many of these dual sport tires are designed to be used in both locations. They actually have two direction of rotation arrows on the sidewall indicating what direction they should turn depending on if they are mounted in front or rear. Make sure to check the actual manufacturers website to verify.
As far as the Shinko 244, this would also be a good tire. It's a 50/50 tire so it will be a bit better off road than the 705 or K761's. If you do any trail riding, this would probably be a better tire.