'83 KZ550 LTD-C4 Front master cylinder

Looks like this topic was discussed at length, but I'm not finding a OEM, or OEM+ solution. My 1983 KZ550 LTD C-4 (chain driven, single front disc brake) sat for 8 years, and the front master cylinder leaked and the parts got all gunked up. I cleaned it all out, even the seals and piston rod as I am not finding the replacement kit for 43020-1027 online.

Are there any suitable rebuild kits that fit this vintage master cylinder? I bought the 43020-1023 rebuild kit from brake crafters, and the piston rod is 62.7mm vs 61.8mm on what came out of my (I believe original) master cylinder. 

Are there any modern drop in replacements that match the OEM reservoir size, brake line, banjo bolt, brake light switch etc.? 

What are folks doing for brake line replacements? Partillza seems to carry the OEM, at $71.90 ea. However my last order from them (banjo bolt) was the wrong part and I'm skeptical about ordering again. 

I build my own brake lines using Earl's components.  High-quality stuff, and quite easy to build.  Been doing this for 40 years now.  Regarding the master, I'd just look for a decent replacement with a 14mm piston.   There are tons of generic masters in the market, and most are fine.  Brake master cylinders are pretty simple, and even the cheap stuff is generally decent.

what handlebars? and does your m/c have an angled mount? also. the 0.9mm difference matters?