You can find rebuilt ones, but they are expensive. Check with any of the usual suspects. You can also still get the bearings and seals if you are willing to try and rebuild it or have someone do it locally. Mine went out a few months ago and I replaced it with a spare I had from an E28. I wasn't quite a direct bolt on. I had to mix and match some of the mounting hardware. I also ended up having to use banjo bolts with -an fittings and custom hoses since the hose fittings are different sizes and the E28 lower hose woundn't clear the framerail on the coupe. Still cheaper than a rebuilt original. I believe there is a slight pressure difference since the steering seems to require a little bit more effort compared to the stock pump.