Thanx again, Chris.
Mine is split vertically along the venturi. It wasn't evident until the venturi was removed, then a visible gap can be seen on the inside.
I've looked at all the 'bay vendors items and am assessing each to determine the most likely one. I have to order other items from Mecoa for a Kavan 50cc twin, so may order everything together.
My TD .020 has the backplate mount and is bound for a Guillow's 20" Cub. The smallest tank I can find is a 1 oz from Tower, but the Mecoa .3 oz. may work so will check it out. A .020 on 1 oz. would probably run 30-minutes plus! Lol
Oddly, I had considered the repair you mention (kevlar thread/epoxy) when the crack was discovered, as I've used that technique on other items. Thanx for confirming it.