"However, I don't see any attempt to offer inflation-linked securities linked to anything other than the CPI"

 There is no need for those anyway.   Invest in precious metals, energy, infrastructure etc. and keep your cash in gold/silver and/or the currencies of resource-rich countries like Australia, Brazil, Canada, Norway, Sweden etc. and you do have a pretty good hedge against inflation.

"...probably because those who don't trust the government to measure inflation properly trust Morgan Stanley even less. "

 They are all the same.  These days, it is hard to say where the government bureaucratic lies end and the corporate lies begin!

 -d