Unfortunately, after the last EMD update, exact match domains don't rank too well for the matched keywords. Partial match domains however, still rank very well.
A co uk domain would have a better chance at ranking for traffic from UK and correspondingly have lesser chance to rank for traffic from other countries. Since you do not want to target only UK traffic, I would suggest going for a commercial domain with a partial match of keywords (name can contain all keywords - just don't let it be an exact match)
Niki