Finally we found it! I am pretty sure the post on Facebook said he made a few (which would have been about 10 or less I think) but I could be wrong, best to ask the new owner. Would make it a super rare mower if there are some more around the place.
It is defiantly not production quality, but it looks good enough to be used by a few local grave yards, wouldn't expect to see these in every backyard though.
Cheers Jack!