Yep, The C92 was a precursor to the C95 (154cc) Benly Touring 150 and we saw Benly Touring 150s in the US market (CA95s) The C92 and C95 has a few differences... but many many common parts.
The swoopy fenders were there before they created the big CA305s so while many will refer to the CA bikes as Dream bikes they came before the 250 and 305 Dreams and the CB variants with a frame...
www.motorera.com/honda has some information, very basic but it is a decent start.
In the Other bikes section I believe Cliff has his C95 rebuilds, he has done a couple. Cliff is in Canada on Vancouver Island (beautiful place) and he goes by the Magpie handle on the forums.
The C92 and CB92 and CA92 all can accept the CA95 or C95 cylinders to bump up the displacement.
The CA95 and CA92 were a higher compression motor if I recall correctly. The CA95 had a powerjet style Keihin carb that was pretty good for its time.
The late CA95s had the option for a Tachometer which required a new side plate with tach gear take off on the upper side of the head. The bikes did not create a ton of horse power but the CB92 was a potent race bike and could have lots of power coaxed out of it in the hands of someone who knew what they were doing.
Be careful on disassembly of course and lots of PB blaster like you are using and heat to help free stuck fasteners.
JIS fasteners everywhere on the bike, so don't try to replace them with the hardware store ISO metric fasteners.
You have something to start with that is rough but pretty much there.
Opt to build it with the higher compression, you will be happier in the long run and bumping up to CA95 specs would be pretty easy for slight bump in power. The CA95 has about 15 bhp and of course that is a pittance... They were good for 55-60mph and maybe 65 with a light rider laying on the tank. The CB175 was a 20hp bike that could do 70 without too much trouble...so for a back road leisurely ride it is a fun bike. The leading link brakes where they stand up when stopping is very different and most who have never dealt with one will find it odd to get used to. The C70 passport had that same design.
Ohio Cycle probably has several OEM and aftermarket stuff for the 92 and 95 models...
Download their list and drop it into an Excel chart and then you can strip out rows that do not apply and then sort it based on other criteria.
Lots of ebay sellers in the far east a well...depends on if you want a nice bike to ride or a restored bike to ride... that will determine what you want to source parts from...
Ask questions and keep plodding along...sooner or later you will arrive where you want to go with the build.
Cliff is one of the more knowledgeable guys on these forums for the bikes. The VJMC email list (separate thing from the VJMC club and website) has several VJMC and non VJMC members who know these bikes very well. Worth looking at...
There are facebook groups for the C92/CA/CB92 you should look into as well. The CB92 bike's motor would be what I would build if I were going to stay with the 125cc displacement.
Some parts are very expensive...
BTW, the Cloud Silver paint used on these bikes is still available from the Honda Powersports shops in a large spray can that goes for $15-20. Probably a cheaper route than some of the paint suppliers out there. Having a can of that sprayed out and then getting a local paint shop to color match it might work but you run the chance of the metallic particle size being wrong along with all the other little things. Shouldn't need more than 2 cans for all the silver painted things on the bike. But, as you know...95% of a good paint job is prep...so do the prep right with good materials and it will come out nice...just test for compatibility when using different brands on a test panel to ensure they play together nicely. Better to find out before that happens and you have the expense in time and materials to redo it.
You just might be able to clean that paint up very nice and not need to repaint it and just wax it well to keep the original patina...Motor, different story.
Oxalic Acid is a great thing to use to remove rust... you buy it in crystals and mix with hot water...
does not harm paint but removes the rust...