What a deal! If I thought for just one nanosecond that I could get them resized, I'd bite your hand off ..... BUT, 6' 1" down to 5' 5" and 16 stone down to 10 (ish) - hmmmmmmm...... don't think so!
Good luck with the sale. I'm on another Triumph forum if you'd like me to put the information up on there send me a pm.