The Model B-25 triple brush shampooer-polisher was part of the #20-series made by Electrolux (Canada) Ltd. from 1977-79 as a color match to the cylinder models AP200 and AP.  The company is now called Aerus Canada, Inc. and is jointly headquartered with Aerus LLC in Dallas, Texas with store locations throughout the USA and Canada.  Contact an Aerus associate to locate a replacement tank by visiting the Aerus website at aerusvacuums.com for contact information.  Regards.