i sold an engine for 1 of these last year(well this year i suppose but ages ago)
i got £1000 for it and the guy came up from birmingham to get it(im in glasgow)
no wonder he ripped my arm off and drove up to get it same day
i knew the pumps were expensive but didnt realise they were that much
i thought they were around £1500 for a recon

i had 325td a few years ago and when i bought it, it came with a receipt for a new pump from bmw
they only(only ha) took £1900 to s+f it,
it was a e36 so bit older, so may have been a good but cheaper, but 5k sounds like crazy money