That one's an early 1980's Supaswift 'Big Bob', as it looks to be 53cm cut, would be a 'Little Bob' if it was 45cm.
These are still on the market, tho' made in China now. So not rare.
If the deck isn't rusted out, and the wheels are OK, it might be worth fitting a secondhand engine to it. Standard engines were Briggs I/C 4hp and Honda GXV120 or 160.
Past thread with some pics:
https://www.outdoorking-forum.com.au/forum/ubbthreads.php?ubb=showflat&topic=9275
