There is no such thing as a "cut-resistant" chain. It's sold by the foot and they cut it to length, you know. Hmmm. Cutting to length a cut-resistant chain.
It looks like you're still trying to be cheap. Witness the $6 U-lock and now you're looking at an $8.99 padlock for a gym locker.
Use the type of lock you prefer, but especially for locking 12 hours a day at a Metro station, get good, not cheap. In locks, they're mutually exclusive.
My "cheap" U-lock was $45. My "good" one was closer to $150.
I could easily buy a $150 from retailer with some name brand or I could spend $50 on the same function just without the name or advertisement associate with it. Just as I build my own controller instead of buying..same concept same analogy.
Sorry I asked.