Hi Jenny,
Your cover letter is very positive and is an excellent start. I would suggest that you make the following changes:
replace ‘…duties of which…’ with ‘…where duties have included…’
replace ‘I am highly organised as during my employment at ___…’ with ‘I have demonstrated my excellent organisation skills during my employment at___ where…’
Include a second paragraph which details why you want to work for that company, ideally including some company specific information. For example read through their company website or do some research and find out about recent projects or their ethos which particularly interests you to that company.
It wouldn’t hurt to add a ‘Thank you for taking the time to read my enclosed CV. I would be pleased to attend…’
I would also suggest that all of your contact details are included on the cover letter too. It’s not difficult to stick your name, address, telephone and email on the top right hand side of a letter head, and having dealt with many job applications over the years, experience tells me the less work a recruiter has to do, the more likely they are to be keen on your application… and it’s not impossible to imagine your CV getting lost, but if they have your contact details they can always ask for another copy!
Best of luck!