UPDATE::
Still looking for a carb replacement, 37 varieties of knock off carbs, none with a very good rating. So I was trying to fine a Walbro replacement
Mine is stamped WT-403B, I have found NONE at any price with that number!!
The ones I am finding listed for a MS260 are a WT-194 (a little different configuration without the little snorkel thing on top, although "they" say you can switch the top plate out and put that snorkel on it, but will that alter the way it works?? or can I use it as is and use the air filter made for that style? ) And I've also found a WT-426-1, also says it is for the MS260, and has the snorkel , looks the same but still wrong number.
Are these different or just for different years, I can also find no cross-reference for these things. Apparently mine is an "intellicarb" or something, but I find little reference to it.
UPDATE TO THIS UPDATE
After all morning doing research, and reading a lot of posts over on the arborist site I ordered a carb. I ended up ordering the WT-426, which apparently the same as the WT-194 but an earlier model AND has the little snorkel on it so it more closely matches mine, and was designed for the snorkel. (apparently the snorkel is part of the intellicarb set up
Should be here in 4 days so stay tuned!
Also (going back a few posts) going through the bag of parts that came with my disassembled saw was a new fuel line and a new fuel filter, apparently they were going to start work on my saw when I told them no and left them in there..so I got a couple freebies.. that's my story and I'm sticking to it!!