moee,
I'm not an expert, but it looks good enough to me.
On item 3 there appears to be a word missing in the end of the sentence.
Make sure:
1) It's printed in company letterhead
2) Attach a business card of the person signing the letter
3) Include the number of hours worked per week - if this varied a lot, indicate an average
4) Get a few copies (you may need one when you get in Canada and go look for a job, or for other purposes...)
