The Zefal HPX design is proven and has remained unchanged for many years which means that spares support is very good. You can buy almost every part inc rebuild kits and the wing lever. This is similar to some Silca pumps.

My old Blackburn mini pump needed a spares kit but the design had been altered very slightly.
If you are going to buy one of the modern "designer pumps" that will be upgraded within a few years, then buy some spares kits at the same time.