120/90 16 rear with 100/90 19 front cb400t set of tires?

So I've been learning about tires for all of 30 min but I did read the articles posted in this section. I think I want to go with a 120/90 16 on the rear because the chain guard won't let me run a 130/80 (yes i want to keep the chain guard) anyone recommend a decent brand or places to look at for these tires? I would like to get a set and preferably in the lower price range like the shinko 712's

Ive used www.denniskirk.com to find tires before, but they don't sell Shinko tires. Motorcycle Superstore probably has what you need.

How wide is your rear wheel? 120/90-16 isn't an easy size to find.

the current tire reads 4.60 which i think translates to 115. I found the 120 but didn't have a matching 100/90 18 for the front but I've decided I'm just going to trim the inside of the chain guard and run a 130. now I need to start looking for tires for my 78 cm185 project

No, the width of the rim. It should be stamped somewhere - I want to say it will look like "2.15-16" or similar.

so on my quest for tires, I came across this awesome chart. I might post it so others can see it. it helps figure out what size tire can go on your rim and has both measurement styles in case you are not sure of conversion. of course, mind your clearance inside your swing arm.
http://www.dropbears.com/u/utilities/tyrerim.htm