The 8-in vases are scarce. If you have my first book (Chance Expressions) then on pp.100 & 109-111 there's a breakdown of all the handkerchief vases and posy bowls, by pattern, size and colour. This was based on a sample of 1,331 items listed on eBay over a period of 18 months. At the time of writing (late 2006) there were only four patterns made using this size.
The problem is collectability. They are so large it's impractical to show them in quantity unless you have plenty of shelf space.