Unfortunately, after an epic search, I was unable to find the paper certificate. I had it once upon a time but I have no idea where it resides now and I never kept the original box. It is, of course, unquestionably authentic Steiff. The quality alone is testimony to it and it came from my mum's little gift shop. She used to sell Steiff up until she retired.
The item "STEIFF FATHER SANTA BEAR WITH REINDEER AND WOODEN SLEIGH Limited Ed #670565" is in sale since Saturday, November 11, 2017. This item is in the category "Dolls & Bears\Bears\Steiff". The seller is "barrybears2002" and is located in Edinburgh. This item can be shipped to United Kingdom, Antigua and barbuda, Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Australia, United States, Russian federation, Canada, Brazil, Japan, New Zealand, China, Israel, Hong Kong, Norway, Indonesia, Malaysia, Mexico, Singapore, South Korea, Switzerland, Taiwan, Thailand, Bangladesh, Belize, Bermuda, Bolivia, Barbados, Brunei darussalam, Cayman islands, Dominica, Ecuador, Egypt, Guernsey, Gibraltar, Guadeloupe, Grenada, French guiana, Iceland, Jersey, Jordan, Cambodia, Saint kitts and nevis, Saint lucia, Liechtenstein, Sri lanka, Macao, Monaco, Maldives, Montserrat, Martinique, Nicaragua, Oman, Pakistan, Paraguay, Reunion, Turks and caicos islands, Aruba, Saudi arabia, South africa, United arab emirates, Ukraine, Chile.