SX50 and Teleconverter

I've managed to connect my trusty Oly B300 teleconverter to the front of the SX50's lens, using a couple of stepdown rings. The optics seem promising, as much as I can tell from hand-holding.

I want to do some serious testing of this system by placing it onto a tripod. The thing is so "front-heavy" however, that I'm concerned for the stress/strain integrity of the SX50's body if I simply attach the unit's base, to a simple tripod screw.

Is anyone aware of a lens ring support for the SX50... enabling it to be balanced on a tripod? Such a support would have to be narrow enough and of the right internal diameter to fit onto the fixed part of the lens barrel immediately in front of the flash. Any ideas are much appreciated.