I bought an MVE Cryoshipper dewar on ebay a while back without realizing it had a fiberglass neck. It currently has little insulation value as it seems to have lost its vacuum. I do not know the name of the vacuum port on the side for re-pumping and haven't found any useful information online besides a crappy diagram, let alone a place where I can buy an adapter for a reasonable price.
Any info would be helpful. Also I don't have any high vacuum stuff, just a cheapo harbor freight single stage HVAC vacuum pump that claims it can pump down to 75 microns best case scenario. Hopefully that would be a good enough vacuum to hold LN2 again.