Im New Fellas

Im intitally started my business from home and I was using windows xp home sp2. Business began to pick up so I bought windows xp pro sp2. then business really started to pick up and I had to move to a larger area,during the move I (well not me , one of my movers) lost some paperwork including the COA for my xp pro cd. The part that really stinks is that I didnt get a chance to install it on any on my pcs yet ( I have 11, 5 running and 6 about to be assembled. I only need xp pro on at least 3 of them actually..)and I dont want to have to pay another 200 dolars for another copy/ product key. I’ve been searching forums for days, weeks even……What should I or dare I say can I do? Please help…thanks in advance