There is a reference to an unattributed GW countermark with large letters and serifs in J. Gavin Scott's book British Countermarks on Copper & Bronze Coins recorded on a 1797 penny. No picture though.
R.I.P. Wayne, Brad Collecting: Conder tokens 19th & 20th Century coins from Great Britain and the Realm
Comments
Edited to say "nope!"
Doggedly collecting coins of the Central American Republic.
Visit the Society of US Pattern Collectors at USPatterns.com.
Collecting:
Conder tokens
19th & 20th Century coins from Great Britain and the Realm