then find another shop, if there is no new part available then you can't use that shop anyway..... they will tell you to just go kick rocks, sell it or donate it.The shop is a NAPA shop, so they won't work with used parts. They were not concerned about keeping the brake fluid reservoir filled and just keep on driving.
I don't have a part number because there are several part numbers when I search, and I can't confirm which one is for my vehicle . . . 2004 Escalade ESV Platinum AWD 6.0 liter.
if there is no other shop around town, then go out of town $50-75 for used one will go a long way's in price saved for what a new one would have cost you.
get under the truck and write down the numbers on the abs pump and look online, match it up, buy one.