I could use this as a replacement block. The current one I have on my sig rig now.. well let me tell you a short story.
This sig rig is the first thing I ever WC'd and I didn't do a ton of research before buying the kit and putting it together. The only thing besides distilled water I even did with it was throw a kill coil in because everyone was recommending them. It stayed this way for about 6 - 8 months (didn't use my computer much, but it was on 24/7 running some macro programs).. When I finally took the side off and checked the loop it was solid green with some slight black to it, so I took it all apart and I took the block apart as well. The inside of the block looked kinda dirty looking from a glance while I was taking it apart, and when I finally got it apart and looked at it was actually corrosion, and a good amount of it.. I tried some methods like soaking it in vinegar/cleaning with ketchup/etc but with no luck. So without a replacement and without any money I just put it back on there (with new tubing of course) and thew some anti-freeze in the mix of water and some more silver to act as a killcoil and prevent any further corrosion on the block. It still sits there to this day and I've been meaning to get a new block but all my money has been going to bills and car repair lately.
This would make a good replacement!