I think the "partridge" that the standard refers to would be more like "incompletely laced", sort of in between partridge and double laced. I did some searching a few years ago and drew blank too. I bet they were abandoned as the double laced improved. I've never even seen one in Holland.
I would imagine they were partridge as per the standards, so neither? The standard requires a laced edge with a stippled centre that is clear of lacing or pencilling.
There was a vote to de-standardise the partridge last year (2015)
It is commonly believed that the partridge Barnevelders have been extinct in UK for many years. This is not the case, I have some bu they need a little work to bring them up to the proper standard.
Have seen bantam listed on a European breed site