I’m no Pro here, but after a little digging around.
I found pipes banded SIV listed as a Hardcastle.
Vintage Hardcastle Hallmark SIV Baker Street Smoke Shopp Wood Tobacco Smoking PipeGood used condition. Small crack in the wood where the stamp is. As found. View photos.Length: Approx. 5 3/4"Weight: 47g
treasurevalleyantiques.com
Offering a nice Hardcastle or Hardcastles SIV pipe that is in excellent rarely used condition. The silver band is engraved with SIV which is likely the British silver-plate stamp. Hardcastles is own
www.worthpoint.com
Even this one listed on SPC shows the same hallmark stamp as a Hardcastle. It’s hard to see the stamp clearly, but you can see the same V style on it.
pipedia.org