Again, Charlton is not the place to go to look for variety info. The new 2011 edition of Charlton's (65th) will have a Victoria Large Cent variety section in the back and some 93's will be in there. Actually, 1893 is one of the richest of all Victoria dates for varities and the only date that Griffin had 2 rarity 8 coins in. The 1893's have some of the most offset repunches of any year .. some are spectacular. Best to look for are the 9's, with the 3's as well. There are many many spacing varieties, because not just the last digit was repunched into the working dies.... so you have varying gaps between the 8 & 9 and then the final 9 & 8. Again, Charlton will not list anything in the main section of the book that has not been
TPG certified (usually by ICCS) and ICCS certifies a very scant few varieties. There are some wonderful Canadian Coin sites that have people conducting all sorts of research/study into errors, varieties and other specialized niches of collecting. I would recommend the CCRS site as some place you would want to spend some time.