Hmm, interesting. In Australia, for that money you are looking at something like a 530d, when if I'm not mistaken, you can get a base S-Class for the same price in the UK. Damn taxes, damn southern hemisphere. I'd have:
Citroen C6 2.7DTT - $108750 or £60346 without haggling, depreciation would be a nightmare though.
Jaaaaaag XF 3.0DTT Luxury - just over budget, but you could haggle off a few grand.
Land Rover Discovery 4.4 HSE - $92990 or £51612
Merc E250 CGI Avantgard coupe - $94500 or £52000
Kia Magentis 2.0 CRDi - $26990.... wait a minute...