In my opinion none of the ones you list would be ideal.
The bottom two have a cfm rate that is too small, they would not be able to handle any leakage. Also the ultimate vacuum they develop is way more than needed down in the micron range.
The regenerative blower from Grainger develops a maximum vacuum of 70 inches of water. Don't get fooled by this number. It might sound impressive but full vacuum is equivalent to about 384 inches of water. Seventy inches of water is worthless as a vacuum for holding purposes unless you are dealing with entire 4 x 8 sheets of plywood.
In the specs for the CNC Router Vacuum System Air blower I can find no mention of the vacuum it develops. Being a blower it is probably as worthless as the one from Grainger.
The Evacuation Pump, 1/2 HP, 9.53 CFM, 3440 RPM is getting closer with 9.5cfm and a vacuum of 25" Hg but I think it would be marginal.
Using good gasketing this one would hold your full sheets of very effectively because you will have a large total surface under vacuum. Once the parts are separated it might be another story judging from the apparent size and shape of the parts (if I am interpreting your picture correctly) and the parts may slide sideways or lift if you do a perimeter cut using a cutter with any helix.
Actually looking at your parts they may have insufficient surface area for holding by vacuum no matter how good your vacuum is.
The maximum holding pressure per square inch using vacuum is one atmosphere, approx 14.7 lbs per square inch. Less if you live in Denver.
To get this holding power you need a perfect (un-obtainable of course) vacuum of 30"Hg (To be picky it is 29.something). Low volume good quality vane type vacuum pumps will give you this sort of vacuum but at a fairly low cfm so they cannot tolerate any leakage. With these pumps even a pinhole leak can overcome their cfm capacity so they cannot develop any vacuum. Low cost pumps with a higher cfm rate will probably develop less vacuum but will be able to do so with leaks that would overcome the better vacuum rated pumps. Realistically you cannot expect to get much better than 27" Hg unless you have an enormous pump. This vacuum is equivalent to about 13 lb per square inch of holding power. If you have this acting on a square foot of surface you have an impressive 1900 lbs holding the material down. If the material is rigid it will be very difficult to lift or slide with this type of holding force. However if the material is flexible it is not difficult to peel up and edge to create a leak and then the entire holding force is gone. Naturally when you start moving to smaller areas the total holding force is reduced and this is when sideways movement becomes a possibility. The cutter exerts the same force whether it is running a cut down the side of a piece one square foot in area or five square inches. But the five square inches is only held down by about 65 lbs of force so it slides sideways.
Do your parts have holes? If so you may be better off considering holding them down with screws. You could use a low vacuum to hold the enter sheet of material down onto a sheet of 1" MDF spoilboard for drilling all the holes. Then insert screws while the vacuum is still on and finish cutting them all out. The cut tracks in the MDF would actually serve as vacuum channels for the full sheet meaning you would be able to get by with low vacuum rather than having to suck through the spoilboard.
An open mind is a virtue...so long as all the common sense has not leaked out.