tbf, i've tended to find any lube on the hop rubber will wear off after the first half mag or so, less if you've done a decent job drying it off before installation.
that said, hop rubbers are wear components and not particularly expensive relative to the performance you get from a decent setup, so frankly replacing it wholesale would also be my preferred path in this case.
same goes for gearbox seals, especially the piston head although the cylinder head and any nozzle o-rings too if they can't be saved by a little silicone bath.
ofc that's going with the caveat that the op feels confident in their ability to strip, clean and reassemble the box with fresh lubrication, otherwise 'borgs suggestion of a little silicone lube down the nozzle would be the cheapest and easiest route short of getting them booked in with a reputable tech.