One, Two, Buckle my Shoe

Starting last July, I implemented the policy that I would buy my employees one pair of safety shoes per year, in the months of the anniversaries of their hire dates. To make it look less that it benefits me more than them, I skipped myself in July. That means my first pair of company-paid shoes should be arriving shortly. I intended to replace the shoes I bought back when I was still in New Mexico. I noticed the other day, though, that the pair I bought myself here two years ago is coming apart (the sole of my right shoe is separating from the upper part). Aargh! Now do I replace just the falling-apart pair, or do I spend my own money on getting rid of the ill-fitting and older (but not falling apart) pair, too?