I've found on old CB blade antenna in a ham radio shop, and I've bought it.
The antenna is an Intek KA-27, see details on radiomuseum http://www.radiomuseum.org/r/intek_flexible_mobile_cb_anten.html
I's small (80cm) and cheap (14 euros). The blade is cut for 11m CB band, but had an acceptable SWR on 10m when fed against a short counterpoise (1,5m) and mounted on the front BNC connector of my FT-817. Trying the antenna indoors (near my window pointing to east) I've made several 10m QSO in Italy and east europe (LZ, YO). Nice for a cheap blade!
Fotos and further infos in the next days.