Online, there are plenty. But trying to get them to ship to you might be difficult.

http://www.rimfiremagic.co.uk/index.htm
http://www.rudefatdog.com/

There are the two main websites in the UK. I understand that they're reluctant to ship to Ireland. I had to pursuade the lady there (rimfiremagic) to send me very very basic parts about a year ago.

Paddy Fagan or Habour guns (Brian Conroy and Matt McParland http://harbourguns.ie/) in Harbour House in Kildare have their shops open at that range every Saturday. They can get you absolutely anything for your 10/22 you want. They're difficult to do business with over the phone when they don't know you so If you're anyway near Nurney in Kildare I'd suggest visiting there.