"Can we not just buy this stuff off the shelf? ....
You certainly could, but you may also have to buy the full set of the laws, rules, regulations, and possibly local languages of the originating country."
Well, I'm sure one of our European neighbours could sell us a system as a service (hosted in euCloud) that was a close match to the UK's current laws, rules and regulations. Although last time I looked the version with the ability to participate in the revision of laws, rules, regulations and supported languages was around £350m per week...
[Mine's a pint of bitter.. ]