Originally Eden Soaring didn't have any 2-seat gliders and only accepted Silver C and above pilots to fly there. However they now have a K13 and their website gives the impression they will do "training to solo standard and beyond" this summer. However of course you are right - the OP should ring before going if only to check they will be flying!
If the OP fancies a 5-day course then as well as Lasham and Windrushers, there is also Portmoak. It has ridges (hence ridge soaring which often gives a soaring flight when there isn't any thermal to be had), the scenery is fantastic and the standard of instruction and equipment is excellent. So are the chips...
Gliding holiday Courses