I have recently purchased a trailer sailer.

It was sold to me as a Roberts 17 foot Custom.

Phil Hogg a reputable Roberts dealer in Queensland assures me it isn't one of their designs.

Can anyone identify her for me?

Thanks

saw yacht soooo..... like this one a few years ago. the hull was supposed to be cutter rigged with a gaff main , 2 headsails. the builder was impatient and compromised with an alloy masted marconi sloop set up ( which your mast would suggest) the owner reckons it was the stupist thing hed done on the boat. . If hed stuck to a proper befitting rig it would have sail beautifully with that long shallow keel, instead it just used to sail sideways, slowly

possibly a scruffy

this is what your rig aught to look like . short mast mounted well forward , solid wood , dropping into a well in the deck. forestay for upwind performance.
long boomed with a high peaked gaff. with this kind of rig the yacht would be nice and steady and no tending to heel or pond in a sea. would be just as fast as a modern rig.
lowered and furled it could support a massive tent. very simple sheeting,and only 3 lines to adjust the sail,

Look very much like an old Hartley TS 16 or T 18 to me

you can google Hartley TS16 or 18