Might have the wrong end of the stick as I haven't read all posts from the beginning but if you are looking for a vacuum pumps then most compressors can used the other way around, especially the diaphragm pumps.

Clarke Mini Air Compressor - Wiz - Machine Mart Bit pricey but easy to mod, just fix a tube to the intake filter plate and keep the output open. depending on the amount of vacuum you need you could use the smaller 12v tyre inflates or even a fish tank aerator.