They look to be as rare as hens teeth, unless you know anyone in the States that could get one and send you. It might be worth ringing Gemini, to see if they have any idea when they will get stock?

The only thing I could find, that was remotely likely was in Germany, but there are no shaft dimensions, I suspect you would get one shipped from there though.

https://www.beneduracing.com/en/starter-honda/847-honda-engine-ritzel-11-18-benedu-racing-for-all-your-kart-parts.html

Otherwise it might be worth considering going down the 420 chain route?

Peter

Just to have some input. For those who haven't been involved with karting as much as Darren has, 219 is used almost exclusively on high powered racing karts. It's strong, compact and has a huge variety of axle sprockets available and very cheaply. (under £6 usually) and in one tooth increments. I used it because of those factors on Kim, and it was only because the axle moved that I had issues. I would not hesitate to use it again IF I could get the sprocket for the torque converter. If/when I make progress on another CK it will use 35 chain. Proven to be strong enough, lots of axle sprockets (cheaply) and not as bulky to deal with as the 40 series chains, some of which will give clearance issues.
I have just been speaking with Gemini, the supplier that made those sprockets has changed ownership and they say much more difficult to deal with than the previous regime. I am doing some overseas questioning.

Is 15T the smallest 219 your can get to fit the shaft of a Comet TAV?   What size main sprocket are you thinking of using Darren?

I had the same problem.  After hours of searching, discussions with Gemini Karts and Talon Engineering I finally got a quote from Talon for £120 + VAT.  They were obviously not interested in small quantity production.  In the end I made my own by cutting the teeth off the gear provided with the torque converter to form the hub, then I cut a new set of teeth by drilling and filing a piece of steel plate which I welded to the hub.  It sounds a lot more difficult than it really is because the teeth are formed by carefully drilling a ring of holes.  All that said, I think this would be an ideal part for the club to buy in quantity as there appear to be benefits when using 219 chain.