tandems in brisbane

I hoping to find a old tandem but there has been nothing in the classifieds or on the internet.It is only for the occasional sunday ride by the river so thats why i am trying not to spend too much.Has anyone seen one while on there travels?

Old cheap tandems tend to be like riding a wet noodle and are not a rewarding experience. Parts for tandems generally need to be better than for singles due to extra weight and forces involved.

How much is not to much to spend?
This is what we ride

Cheers

Geoff