2 V Blocks, 1 is a Starrett No 568 Replica that is within .0003" of 45 degrees

Description

For sale are 2 ground 45 degree per side V Blocks, with a clamp. I am a 35 yr machinist and I set up a sine vise at 45 degrees in a Bridgeport mill and ran a .0001" indicator across the V's and the block with the clamp was within about .0003" across the 45 degree angle, the other was about .0008" out across the 45 degree angle.
I inspected the sine vise to my Starrett blocks (# 568) which are guaranteed to be within about .0001 or .0002" accurate, so I know my inspection setup is accurate. (shown in the last 3 pics). The 45 degree angle is very accurate on the block with the clamp, so it is an excellent quality V-block.
If the used V-blocks you are buying have not been inspected by a professional, how do you know what you are buying? (unless you do not care if the angle is accurate and you are going to re-grind them anyway).
Both are unmarked, so I do not know where they were made.The one with the clamp is about  2.5" x 2.757 x 2.0 high ", and was made to replicate the Starrett V-blocks No 568,  and the other is about 2.536 x 1.761 x 1.534". The one with the clamp that replicates the Starrett 568 blocks was very accurate across the 45 degree angle as it was only about .0003" out. The other block is a bit rough on the 45 degree surface, but yet OK to locate most parts, and due to having a larger "V", it can hold larger dia parts. If you would like this block re-ground to be more accurate like the block with the clamp, just ask and I can re-grind the "V" within about .0002" of the 45 degree angle for about extra-just email me and ask. I would not recommend re-grinding the block with the clamp, as it is already very good. The block that could use re-ground also has a .375 dia hole in the center of the "V", and 2 set screw holes (with set screws in them) coming into the .375 dia hole to hold a post for a stop.
I have a few more V-blocks for sale also that I also inspected, so please check them out also.
Thanks for looking.