I killed the master cylinder

[laruetou2]

I'm new to Chinese bikes and new to this forum. Just bot a BD125-10 - it came with many upgrades. No operator manual (which sucks). No parts manual (which sucks).

Was fooling around with it and put my thumb on the round seal or panel (about 5/8" circular) on the aft side of the master cylinder reservoir. It broke and fluid began dripping out. Bad design, but who am I to advise Honda or the clone makers.

Questions:
1. Do I have to pay for an operator's manual. I'm generally used to finding manuals (all kinds) online with no charge for download.
2. Same with parts manual.
3. Can I repair this master cylinder by replacing the plastic panel or do I need to buy a new master cylinder. Where do I get the panel or the new master cylinder? Is there a spec?

Thanks to all in advance,
Larue