I purchased a Sig Compact slide with the Sig Zero Red dot and suppressor sights. I was told by a gun store that purchasing a Sig Compact threaded barrel will not work on this slide.

Rather than having to buy a whole new slide assembly, is there a threaded barrel that will work with this slide? Thanks

There are many SIG Compacts. Which one are you talking about?? But, in general, a threaded barrel for a certain model will fit to that model. Sometimes, minor fitting might be needed, but most of the time, it's just a drop-in w/o problems.