Turbo Braking Master Cylinder with ABS

[Jotronic]

Prices for master cylinders with ABS have skyrocketed. I'm in the middle of an upgrade for my 88 with ABS by installing 996TT calipers and bigger discs and I wanted to install a new MC just as a preventative measure in case my old internal seals are too old to hold the pressure after having a full fluid flush and refill. I can't find any rebuild kits and a new unit is ridiculously priced. Non ABS units are cheap, but I need one for an ABS setup.

What is everyone using for master cylinders if they aren't using an OEM unit? I know of the BMW 750iL unit. That requires a T fitting for the front line and the internal pistons are both 25mm compared to the stock 951 unit at 23mm and 19mm respectively. The MC is cheap at 200 bucks more or less, 1/4 the price of a new 951 OEM unit. Is anyone using this and if so, how is it working out with your ABS and the stock proportioning valve?