Got a beetle to fix up the people had it for ages they had no papers and didn't give bill of sale or anything it was sitting in there yard so I don't want to start doing anything to it till I know that once all the work was done that I can get a blue slip and get it registered ????

Yes it can be done.

A signed letter from them with drivers licence number and address that states it was theirs to sell to you for $X ...... Better still the previous on a statutory declaration.

And I think there was the option of doing a stat dec on your own if you cannot contact them any longer

As always, just check with your local RMS office tho