Hey Gary,
RS Paints do do ? the tank colours but they will not post to Ireland, If you know someone in the UK that can post it, get them to buy it and send it on.
www.rspaints...or something. Ring them - Have your frame No. ready as they will match the paint according to the year and model and suggest probably three of the standard colours for the bike and it's time. (Have not used them though....I just picked a "similar" colour from some swatches in the paint shop, the concours people are horrified, but you have to look really close to spot it.)
As for High temp paint... Someone pointed out here some time ago that if that area of your engine gets hot enough to warrant high temp paint ...you have other things to worry about.
I painted my engine casings with Plastikote alluminium and laquered over it. three years later and it seems as good as new. (Most car accessory shops do Car exhaust paint in Silver or black but they're manky. The sprocket cover, clutch cover, rocker cover and the head...I polished back to the alluminium and keep them polished with Autosol etc. same with fork legs. mine were particularly bad so I microblasted them first, the rest.....Sore fingers
Architectural & Industrial coatings are in Cork and they do powdercoating so long as the frame etc have been sandblasted first (Any colour any finish). 021-4962240 They done mine for 80 Euro well worth the effort of removing EVERYTHING first. There's also supposed to be somebody in Limerick direction or Clare.
For parts...www.david silver spares in the UK you can price the bits on the web first