[vintagetoppsguy]

You're probably looking at ExMt cards. Even is you get NM cards, it going to cost you $5 to grade them. I don't know what a NM '58 Topps common goes for, but I will guess about $10. Does that sound right? So, you're only making $5 off each card = $60 (assuming you would be grading them for re-sale). I am guessing the racks cost you more than that. If I were you, I would try to get my money back. If not, re-list them on eBay. If you don't have a lot of money into them, it may be worth keeping them just because they make an interesting conversation piece. Good luck with whatever you do.

Edited to add: please post some scans if you decide to bust them open.