Just as well it did blow by the sound of it Dave. At least it alerted you to the alternator regulator issue, hopefully before it damaged the battery.
It's not too difficult to fit a new regulator within alternator. Stripping down and removing old one as pattern for replacement should be easy although soldering iron may be needed. A good auto electric supplier should be able to provide replacement and they all regulate to around 14.4 volts. Keep a close eye on isolating washers though as leaving one out could spell disaster.
