I bought a couple from two different sources a while back (now out of them).
You need to understand ahead of time that these barrels are not necessarily just a drop in and fire proposition. You might have to do some minor fitting, for example by modifying the extractor a wee bit, or getting a correct barrel to barrel bushing fit. Stuff you can do at home, or any competent gunsmith can do quickly.
There are special mags for the 9mm to accomodate its slightly shorter length. The 7.62x25 mag will often "work", but can be the cause of feeding problems if used for 9mm.