m800 stalling when warm

Hi Guys, Its been a while, and iv'e put a few miles on the old girl.
But I have recently developed a stalling issue when shes warmed up, on a recent ride in the nice weather we are having here in the UK, stopped at a red light and she went all lumpy and stalled, it started straight back up no issues, but again very lumpy, with a bit of throttle kept her running and pulled off. This kept happening all the way home 40 miles ish.
Got home and had a quick look around to make sure all was still connected etc, whilst pressing on the front cylinder plug cap I got a slight tingling sort of shocking sensation, nothing like the belt you get from a plug but enough to think that's a little strange.
Since this iv'e whipped the plugs out, look ok? gap is 0.9 as should be leads look ok. Had a look through a few posts and will deffo blow and vac the air filter out, seems they look clean but could be part of the issue.
So my question is could the insulation be breaking down on the HT lead/ignition coils, would that cause the slight shock from the lead/cap? and would that be causing the stalling issue. Next thing should I replace the coils with aftermarket or genuine parts?
Any info would be a great help ladies and gents, thanks in advance.
Shes an intruder m800 2008 model. 

Kind regards.
Jamie.

Hi Guys, 
Don't suppose anyone knows where to buy the ignition packs?
I've done the usual searches and all the aftermarket ones don't seem to be for my bike?
Cheers.