Peter, I have some 7266 in 16mm. I can expose say 2 or 3m and post it up to you if that helps you out?
While 35mm B&W reversal is not commonly available from all film manufacturers, there are two relatively easy to come by. Foma R100 and ADOX Silvermax.
In Sydney you should be able to get FOMA R100 from Chris at BlancoNegro in 35mm, 16, and double standard 8. He has looked after me in the past with the Foma film in 35mm.