Europek..
there is a medium term gilt future you can use which is roughly 5y duration. very illiquid, but the option is there for you since you are in a long-term macro set up.. there is also a short term duration gilt future as well. i use both all the time for long term strategies.
.. bid ask spreads "rarely" touch so.. just use a program to execute automatically when b/a spread narrows to a "somewhat" favorably slippage level.
if you want to be active.. forget about it.. daily-plus time frames only do to lack of current participants.
& just one quick thought although you already know this.. uk shorter term durations can really move too!
good hunting