This might be a better bet: britishshop.pl/en_GB/index
Everything at that shop is horribly expensive.
For an extra three zloty you can get nearly twice as much on Allegro
Piotr i Pawel have some HP sauces too
M&S do a brown sauce that is perfectly acceptable and only about 6zl a bottle.
But the mutt's nuts when it comes to brown sauce is this one:
Sadly it's an 'Amazon only' job in Poland.