Do you mean the applet? At 480 exact google local searches a month not a great search volume keyword and not quite sure if there is a demand for ones that are paid for most seams to be free...? You would probably need to find a company that writes? them and charges to be able to get any interest in it... Then price would I suppose depend on what they sell them for…?
Yes , bookmarklets are basically a couple of lines of Javascript code which are given away for free.
They have numerous uses, the most popular at the moment is search.
Any opinion as to value ?
Unless there popular with the iphone ipad etc them can’t see as there given away mostly free you could sell it..? If you could find a company that’s sells them in the uk try for a few hundred pounds not sure there are any and if there aren’t then you’ll never sell it...