Markturbo

I measured the carb inside diameter with calipers and it's 28mm, i read there are also 26mm Mikuni's? If Im buying used online how can i confirm im getting 28mm and not 26mm?

The top cap threads on my left (choke side) carb body are stripped, I confirmed its the body and not the cap. I'd like to find just a replacement carb and swap my parts into it. I'd like to find the one replacement and not buy two new carbs and keep the stock Mikuni's. The carb is stamped "2GU 01" and I've seen some others stamped "2GU 00", what's the difference? Any other options then Ebay for trying to find a good used carb? My Banshee is a 2001 and Im in Canada if that makes any difference as to which carbs are on it. Thanks for the help.