1991 Hyundai brake fluid leak

Brakes problem
1991 Hyundai 4 cyl Wheel Drive Type unknown Automatic unknow miles

91 or 92 scoupe:

(I believe it is front wheel drive)

this junker started leaking fluid between the brake line (the one closer to tthe front of the car) and the master cylinder. Here is the part that throws me, there is a green anodized component that threads into the master cylinder that seems to be a check or flow valve. The other end is where the brake line is threaded into. Inside this check valve is a blue anodized mandrel that has two o-ring seals that are shot, hence it is leaking out a little bleed hole that is covered by an external o ring.I cannot find this part on any web or parts location. I am wondering if this is not the correct master cylinder for this vehicle. Can I just use a M10 to M15 (i think this is the size of fitting ito Master Cyl) adapter to make it work safely? Anyone have any idea?
thanks in advance