Nashbar is just a brand, they don't make anything... So Who made the pump ,
badged to have their name on it , Is unknown to me..
Call them up and ask? (it's a division of Performance Bike Corp, now)

generic answer , since I don't own one..

If the plunger is removable, and If the pump cup is Leather..

then I can say .. I kept the leather pump cup from drying out with grease..

I happened to have a tub of Boot Grease handy..

on 2 pumps, from other sources, for 3+ decades..







....