£5 + P&P (approx. £2.50 via 1st class recorded) is ok with me.
Unwilling to let the grip go for £5 all in. Sorry.
I'm assuming that you just want the regular grip and not the NT style one (it's a spare one that DYE UK kindly sent out to me, which otherwise would have cost me a ludicrously priced £14.99!!, so I definitely will not be letting that go for £5).
Having said that, if you still have your old worn-out grip, just contact DYE UK and speak to Rich/Ash about perhaps getting a free replacement (as long as you provide evidence of the damage/wear&tear).