Are you lookin for a Mk VII or XIX? New or used? If you want a new XIX barrel you can get them from magnum research, however it won't be cheap .
Other than checking auction sites, doing a google search would be your best bet.
Several years ago cdnn investments had brand new Mk VII barrels for about %40 of the cost of factory new from magnum research. I got a 10" .357 MK VII barrel for $139.
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"Nothing tastes as good as skinny feels" K. Moss
You can NEVER be too rich or too thin.
Life is not a journey, but a series of unplanned detours...
Perfection: is not a goal---it's a demanded expectation.