I visited Ware in the summer of 2002 to try and find where the firm was located. The street name gave an obvious clue! The grey building on the right is the main part of the original factory.
It was now 'Swains Mill'. The building in front has signs that it could be the original brick office building in a cut-down form.
Sadly, it was sold for redevelopment in 2016 and was subsuquently demolished. The google street view dated March 2019 at the same place as the top image shows housed under construction on the site.