Front Master Cylander ID / Issues

Trying to confirm/disprove whether the front master cylander setup on my bike is original or not...I suspect not. Bike is a '78KZ1000A w/ dual front disc setup. The unit seems to be a "Magura" and there are markings "16" and "00' on the plunger housing. It has a rectangular reservoir.

Front brake needs something...the handle/plunger is very slow to return to uncompressed position and I'm having no luck getting the reservoir to actually push fluid into the line in order to bleed the breaks. Lines seem clear, I'm able to push air through them, so I'm guessing I'm having some sort of issue with the spring, the diaphragm, both...or something. I'd like to order the parts to rebuild...but I don't know what/where.

Thanks for any help.

K&L Supply might have what you need (rebuild kit) but they sell to dealers only. Check to see if your return fluid hole is not obstructed inside the resevoir. Magura was not OE on that bike. Magura makes a lot of replacement M/C for bikes. You might check with Jeff at Z1 Enterprises.

Managed to track down the model info, Magura 0122020 16mm if anyone's interested. Seem to be a standard aftermarket for lat 70's Japanese dual disc setups.

Thanks.