Hello Les
Your button with a crown over 'GR' is generally considered to be a generic pattern used by several militia units.
There were several button makers named Jones (probably all related) who used a 'Jones Dublin' backmark and variations thereof, over a period of time - Wm Jones, Edward Jones, W & E Jones, E Jones & Son. I would think your button dates to around 1810 give or take a few years.
I can't find the other pattern button in Joe McDonnells book on Irish Militia buttons but it could either be a new, as yet unrecorded pattern, or not Irish Militia at all but for a British Militia unit. There are a lot of early militia buttons shown here -
http://asahelena.wixsite.com/militarybuttons/buttons
Well worth browsing through if you have a few spare hours!
Roger