more likely to be the pump itself getting gummed up with ‘varnish’ since the bike has likely spent long periods standing, given age and mileage. You should be able to put 12v directly onto the pump and see if it works.
any help?
http://ca-cycleworks.com/fp-duc.html
you’ll likely get a bill for VAT & 6% import duty before it clears customs but it beats £790