A little more information on this UK glass producer:http://uk.trademarkdirect.co.uk/s-e-r-i-v-e-r-r-e-1120314
This trademark dates to 1979, and is useful for dating these products. Sadly, I don't know what the Seriverre product actually is! It might refer to the slumped, textured glass range, with printed transfers it produced.
The company was formed in 1972 according to a company check:
Address: High Barn, West End, Northleach, Cheltenham Gloucestershire, GL54 3HG
Previously: EUROANGLIA LIMITED
Company Status: DISSOLVED
Company Number: 01081046
Company Age: 43 Years - Incorporated on 09 Nov 1972
But when was Pettis dissolved? With this data, we then have a complete dateline of its glassware.
Other associated link: http://www.glassmessages.com/index.php/topic,11499.msg83841.html#msg83841