http://www.agentprovocateur.com
Highly recommended! Have never had any issue with them delivering to SIN, either. But a bit of a tip, which is a little naughty, make sure you buy them in batches <$300, that way you don't pay the duty/GST thingie here.
They have "larger" cup sizes also.
Alternatively, where back in Aus are you getting married? I might be able to suggest some stores for you. Might be short notice, but you never know!
Ms. C shot me this the other week - she was pretty impressed:
http://www.indulgefashion.com.au/depart ... w-Lingerie
Posted by another male who happens to know such things, but unlike some others, does not wear such items
Mr. P