How about one of these?
https://www.ebay.co.uk/itm/Radiator-...MAAOSw2zlXhmDz
Has plenty of power and is only a little smaller than the original so that could be made up with some foam if it was needed.
Being VW it should be available world wide and be reliable, there is also plenty of copies of this fan available if you wanted to go that route, I suspect the mounting would need fiddling but nothing a few washers could not fix.