Is there a major difference between College Physics: A Strategic Approach and the international edition of the same book? I'm looking to buy the textbook for PHYC10007.
Nearly always the international edition is the same book. There might be a different cover (it might be a softcover,) some chapters might be in the wrong order, and the order of end-of-chapter questions are probably randomised. Occasionally, the book is in black and white, and it may be on lower quality paper.
There's always a substantial discount - if it's big, go for it. Although you probably don't need the textbook. Just borrow it from the library when you need it, or photocopy the pages (exercises) you need.