SAG = Society of Australian Genealogists, in Kent St., Sydney. info [at] sag.org.au (change [at] to @)

You should ask the IOM Registry by email through their "Contacts" whether they accept money orders or other methods of payment if you are not a member of SAG, and ask what is included in death certs at that time.

If not a member you could try asking SAG whether you can buy a sterling cheque if you buy a day pass to their library. Not a lot about the IOM, but good holdings including on fiche/film and online for England and Ireland, and some good sources for Scotland - fair for NZ and worldwide incl military records. Very good Aust. holdings.

As previously mentioned, this message gave Jane's surname as KILLEY - it doesn't make this necessarily wrong that their son married someone (Margaret) of the same surname, unless the writer was referring to son William, which isn't clear as she gives no dates:
www.isle-of-man.com/cgi-bin/interests/genealogy/bulletin/index.pl?noframes;read=505051

Sue